Use AssertJ’s exception assertions rather than fail

Closes gh-15761

spring-boot-project/spring-boot-actuator/src/test/java/org/springframework/boot/actuate/endpoint/invoke/convert/ConversionServiceParameterValueMapperTests.java

 /*
- * Copyright 2012-2018 the original author or authors.
+ * Copyright 2012-2019 the original author or authors.
  *
  * Licensed under the Apache License, Version 2.0 (the "License");
  * you may not use this file except in compliance with the License.
@@ -28,7 +28,6 @@ import org.springframework.format.support.DefaultFormattingConversionService;
 
 import static org.assertj.core.api.Assertions.assertThat;
 import static org.assertj.core.api.Assertions.assertThatExceptionOfType;
-import static org.junit.Assert.fail;
 import static org.mockito.ArgumentMatchers.any;
 import static org.mockito.BDDMockito.given;
 import static org.mockito.Mockito.mock;
@@ -61,15 +60,14 @@ public class ConversionServiceParameterValueMapperTests {
 		given(conversionService.convert(any(), any())).willThrow(error);
 		ConversionServiceParameterValueMapper mapper = new ConversionServiceParameterValueMapper(
 				conversionService);
-		try {
-			mapper.mapParameterValue(new TestOperationParameter(Integer.class), "123");
-			fail("Did not throw");
-		}
-		catch (ParameterMappingException ex) {
-			assertThat(ex.getValue()).isEqualTo("123");
-			assertThat(ex.getParameter().getType()).isEqualTo(Integer.class);
-			assertThat(ex.getCause()).isEqualTo(error);
-		}
+		assertThatExceptionOfType(ParameterMappingException.class)
+				.isThrownBy(() -> mapper.mapParameterValue(
+						new TestOperationParameter(Integer.class), "123"))
+				.satisfies((ex) -> {
+					assertThat(ex.getValue()).isEqualTo("123");
+					assertThat(ex.getParameter().getType()).isEqualTo(Integer.class);
+					assertThat(ex.getCause()).isEqualTo(error);
+				});
 	}
 
 	@Test

spring-boot-project/spring-boot-actuator/src/test/java/org/springframework/boot/actuate/trace/http/reactive/HttpTraceWebFilterTests.java

 /*
- * Copyright 2012-2018 the original author or authors.
+ * Copyright 2012-2019 the original author or authors.
  *
  * Licensed under the Apache License, Version 2.0 (the "License");
  * you may not use this file except in compliance with the License.
@@ -36,7 +36,7 @@ import org.springframework.mock.web.server.MockServerWebExchange;
 import org.springframework.web.server.ServerWebExchangeDecorator;
 
 import static org.assertj.core.api.Assertions.assertThat;
-import static org.junit.Assert.fail;
+import static org.assertj.core.api.Assertions.assertThatExceptionOfType;
 import static org.mockito.BDDMockito.given;
 import static org.mockito.Mockito.mock;
 
@@ -123,19 +123,14 @@ public class HttpTraceWebFilterTests {
 	@Test
 	public void statusIsAssumedToBe500WhenChainFails()
 			throws ServletException, IOException {
-		try {
-			this.filter
-					.filter(MockServerWebExchange
-							.from(MockServerHttpRequest.get("https://api.example.com")),
-							(exchange) -> Mono.error(new RuntimeException()))
-					.block(Duration.ofSeconds(30));
-			fail();
-		}
-		catch (Exception ex) {
-			assertThat(this.repository.findAll()).hasSize(1);
-			assertThat(this.repository.findAll().get(0).getResponse().getStatus())
-					.isEqualTo(500);
-		}
+		assertThatExceptionOfType(Exception.class).isThrownBy(() -> this.filter
+				.filter(MockServerWebExchange
+						.from(MockServerHttpRequest.get("https://api.example.com")),
+						(exchange) -> Mono.error(new RuntimeException()))
+				.block(Duration.ofSeconds(30)));
+		assertThat(this.repository.findAll()).hasSize(1);
+		assertThat(this.repository.findAll().get(0).getResponse().getStatus())
+				.isEqualTo(500);
 	}
 
 }

spring-boot-project/spring-boot-actuator/src/test/java/org/springframework/boot/actuate/trace/http/servlet/HttpTraceFilterTests.java

 /*
- * Copyright 2012-2018 the original author or authors.
+ * Copyright 2012-2019 the original author or authors.
  *
  * Licensed under the Apache License, Version 2.0 (the "License");
  * you may not use this file except in compliance with the License.
@@ -37,7 +37,7 @@ import org.springframework.mock.web.MockHttpServletRequest;
 import org.springframework.mock.web.MockHttpServletResponse;
 
 import static org.assertj.core.api.Assertions.assertThat;
-import static org.junit.Assert.fail;
+import static org.assertj.core.api.Assertions.assertThatIOException;
 import static org.mockito.BDDMockito.given;
 import static org.mockito.Mockito.mock;
 
@@ -106,25 +106,24 @@ public class HttpTraceFilterTests {
 	@Test
 	public void statusIsAssumedToBe500WhenChainFails()
 			throws ServletException, IOException {
-		try {
-			this.filter.doFilter(new MockHttpServletRequest(),
-					new MockHttpServletResponse(), new MockFilterChain(new HttpServlet() {
-
-						@Override
-						protected void service(HttpServletRequest req,
-								HttpServletResponse resp)
-								throws ServletException, IOException {
-							throw new IOException();
-						}
-
-					}));
-			fail("Filter swallowed IOException");
-		}
-		catch (IOException ex) {
-			assertThat(this.repository.findAll()).hasSize(1);
-			assertThat(this.repository.findAll().get(0).getResponse().getStatus())
-					.isEqualTo(500);
-		}
+		assertThatIOException()
+				.isThrownBy(() -> this.filter.doFilter(new MockHttpServletRequest(),
+						new MockHttpServletResponse(),
+						new MockFilterChain(new HttpServlet() {
+
+							@Override
+							protected void service(HttpServletRequest req,
+									HttpServletResponse resp)
+									throws ServletException, IOException {
+								throw new IOException();
+							}
+
+						})))
+				.satisfies((ex) -> {
+					assertThat(this.repository.findAll()).hasSize(1);
+					assertThat(this.repository.findAll().get(0).getResponse().getStatus())
+							.isEqualTo(500);
+				});
 	}
 
 	@Test

spring-boot-project/spring-boot-autoconfigure/src/test/java/org/springframework/boot/autoconfigure/condition/OnBeanConditionTypeDeductionFailureTests.java

 /*
- * Copyright 2012-2017 the original author or authors.
+ * Copyright 2012-2019 the original author or authors.
  *
  * Licensed under the Apache License, Version 2.0 (the "License");
  * you may not use this file except in compliance with the License.
@@ -31,7 +31,7 @@ import org.springframework.context.annotation.ImportSelector;
 import org.springframework.core.type.AnnotationMetadata;
 
 import static org.assertj.core.api.Assertions.assertThat;
-import static org.junit.Assert.fail;
+import static org.assertj.core.api.Assertions.assertThatExceptionOfType;
 
 /**
  * Tests for {@link OnBeanCondition} when deduction of the bean's type fails
@@ -44,21 +44,20 @@ public class OnBeanConditionTypeDeductionFailureTests {
 
 	@Test
 	public void conditionalOnMissingBeanWithDeducedTypeThatIsPartiallyMissingFromClassPath() {
-		try {
-			new AnnotationConfigApplicationContext(ImportingConfiguration.class).close();
-			fail("Context refresh was successful");
-		}
-		catch (Exception ex) {
-			Throwable beanTypeDeductionException = findNestedCause(ex,
-					BeanTypeDeductionException.class);
-			assertThat(beanTypeDeductionException)
-					.hasMessage("Failed to deduce bean type for "
-							+ OnMissingBeanConfiguration.class.getName()
-							+ ".objectMapper");
-			assertThat(findNestedCause(beanTypeDeductionException,
-					NoClassDefFoundError.class)).isNotNull();
-
-		}
+		assertThatExceptionOfType(Exception.class).isThrownBy(
+				() -> new AnnotationConfigApplicationContext(ImportingConfiguration.class)
+						.close())
+				.satisfies((ex) -> {
+					Throwable beanTypeDeductionException = findNestedCause(ex,
+							BeanTypeDeductionException.class);
+					assertThat(beanTypeDeductionException)
+							.hasMessage("Failed to deduce bean type for "
+									+ OnMissingBeanConfiguration.class.getName()
+									+ ".objectMapper");
+					assertThat(findNestedCause(beanTypeDeductionException,
+							NoClassDefFoundError.class)).isNotNull();
+
+				});
 	}
 
 	private Throwable findNestedCause(Throwable ex, Class<? extends Throwable> target) {

spring-boot-project/spring-boot-autoconfigure/src/test/java/org/springframework/boot/autoconfigure/jdbc/DataSourceInitializerInvokerTests.java

 /*
- * Copyright 2012-2018 the original author or authors.
+ * Copyright 2012-2019 the original author or authors.
  *
  * Licensed under the Apache License, Version 2.0 (the "License");
  * you may not use this file except in compliance with the License.
@@ -47,7 +47,7 @@ import org.springframework.jdbc.core.JdbcTemplate;
 import org.springframework.util.ClassUtils;
 
 import static org.assertj.core.api.Assertions.assertThat;
-import static org.junit.Assert.fail;
+import static org.assertj.core.api.Assertions.assertThatExceptionOfType;
 
 /**
  * Tests for {@link DataSourceInitializerInvoker}.
@@ -178,16 +178,13 @@ public class DataSourceInitializerInvokerTests {
 
 	private void assertDataSourceNotInitialized(DataSource dataSource) {
 		JdbcOperations template = new JdbcTemplate(dataSource);
-		try {
-			template.queryForObject("SELECT COUNT(*) from BAR", Integer.class);
-			fail("Query should have failed as BAR table does not exist");
-		}
-		catch (BadSqlGrammarException ex) {
-			SQLException sqlException = ex.getSQLException();
-			int expectedCode = -5501; // user lacks privilege or object not
-			// found
-			assertThat(sqlException.getErrorCode()).isEqualTo(expectedCode);
-		}
+		assertThatExceptionOfType(BadSqlGrammarException.class).isThrownBy(
+				() -> template.queryForObject("SELECT COUNT(*) from BAR", Integer.class))
+				.satisfies((ex) -> {
+					SQLException sqlException = ex.getSQLException();
+					int expectedCode = -5501; // user lacks privilege or object not found
+					assertThat(sqlException.getErrorCode()).isEqualTo(expectedCode);
+				});
 	}
 
 	@Test

spring-boot-project/spring-boot-autoconfigure/src/test/java/org/springframework/boot/autoconfigure/jooq/JooqAutoConfigurationTests.java

 /*
- * Copyright 2012-2018 the original author or authors.
+ * Copyright 2012-2019 the original author or authors.
  *
  * Licensed under the Apache License, Version 2.0 (the "License");
  * you may not use this file except in compliance with the License.
@@ -52,7 +52,7 @@ import org.springframework.jdbc.datasource.DataSourceTransactionManager;
 import org.springframework.transaction.PlatformTransactionManager;
 
 import static org.assertj.core.api.Assertions.assertThat;
-import static org.junit.Assert.fail;
+import static org.assertj.core.api.Assertions.assertThatExceptionOfType;
 
 /**
  * Tests for {@link JooqAutoConfiguration}.
@@ -90,15 +90,10 @@ public class JooqAutoConfigurationTests {
 							"insert into jooqtest (name) values ('foo');"));
 					dsl.transaction(new AssertFetch(dsl,
 							"select count(*) as total from jooqtest;", "1"));
-					try {
-						dsl.transaction(new ExecuteSql(dsl,
-								"insert into jooqtest (name) values ('bar');",
-								"insert into jooqtest (name) values ('foo');"));
-						fail("An DataIntegrityViolationException should have been thrown.");
-					}
-					catch (DataIntegrityViolationException ex) {
-						// Ignore
-					}
+					assertThatExceptionOfType(DataIntegrityViolationException.class)
+							.isThrownBy(() -> dsl.transaction(new ExecuteSql(dsl,
+									"insert into jooqtest (name) values ('bar');",
+									"insert into jooqtest (name) values ('foo');")));
 					dsl.transaction(new AssertFetch(dsl,
 							"select count(*) as total from jooqtest;", "2"));
 				});
@@ -120,19 +115,14 @@ public class JooqAutoConfigurationTests {
 							"insert into jooqtest_tx (name) values ('foo');"));
 					dsl.transaction(new AssertFetch(dsl,
 							"select count(*) as total from jooqtest_tx;", "1"));
-					try {
-						dsl.transaction(new ExecuteSql(dsl,
-								"insert into jooqtest (name) values ('bar');",
-								"insert into jooqtest (name) values ('foo');"));
-						fail("A DataIntegrityViolationException should have been thrown.");
-					}
-					catch (DataIntegrityViolationException ex) {
-						// Ignore
-					}
+					assertThatExceptionOfType(DataIntegrityViolationException.class)
+							.isThrownBy(() -> dsl.transaction(new ExecuteSql(dsl,
+									"insert into jooqtest (name) values ('bar');",
+									"insert into jooqtest (name) values ('foo');")));
 					dsl.transaction(new AssertFetch(dsl,
 							"select count(*) as total from jooqtest_tx;", "1"));
-
 				});
+
 	}
 
 	@Test

spring-boot-project/spring-boot-autoconfigure/src/test/java/org/springframework/boot/autoconfigure/logging/ConditionEvaluationReportLoggingListenerTests.java

 /*
- * Copyright 2012-2018 the original author or authors.
+ * Copyright 2012-2019 the original author or authors.
  *
  * Licensed under the Apache License, Version 2.0 (the "License");
  * you may not use this file except in compliance with the License.
@@ -42,8 +42,8 @@ import org.springframework.mock.web.MockServletContext;
 import org.springframework.web.context.support.AnnotationConfigWebApplicationContext;
 
 import static org.assertj.core.api.Assertions.assertThat;
+import static org.assertj.core.api.Assertions.assertThatExceptionOfType;
 import static org.assertj.core.api.Assertions.assertThatIllegalArgumentException;
-import static org.junit.Assert.fail;
 
 /**
  * Tests for {@link ConditionEvaluationReportLoggingListener}.
@@ -76,15 +76,10 @@ public class ConditionEvaluationReportLoggingListenerTests {
 		AnnotationConfigApplicationContext context = new AnnotationConfigApplicationContext();
 		this.initializer.initialize(context);
 		context.register(ErrorConfig.class);
-		try {
-			context.refresh();
-			fail("Did not error");
-		}
-		catch (Exception ex) {
-			withDebugLogging(
-					() -> this.initializer.onApplicationEvent(new ApplicationFailedEvent(
-							new SpringApplication(), new String[0], context, ex)));
-		}
+		assertThatExceptionOfType(Exception.class).isThrownBy(context::refresh).satisfies(
+				(ex) -> withDebugLogging(() -> this.initializer.onApplicationEvent(
+						new ApplicationFailedEvent(new SpringApplication(), new String[0],
+								context, ex))));
 		assertThat(this.outputCapture.toString())
 				.contains("CONDITIONS EVALUATION REPORT");
 	}
@@ -94,14 +89,10 @@ public class ConditionEvaluationReportLoggingListenerTests {
 		AnnotationConfigApplicationContext context = new AnnotationConfigApplicationContext();
 		this.initializer.initialize(context);
 		context.register(ErrorConfig.class);
-		try {
-			context.refresh();
-			fail("Did not error");
-		}
-		catch (Exception ex) {
-			this.initializer.onApplicationEvent(new ApplicationFailedEvent(
-					new SpringApplication(), new String[0], context, ex));
-		}
+		assertThatExceptionOfType(Exception.class).isThrownBy(context::refresh)
+				.satisfies((ex) -> this.initializer.onApplicationEvent(
+						new ApplicationFailedEvent(new SpringApplication(), new String[0],
+								context, ex)));
 		assertThat(this.outputCapture.toString()).contains("Error starting"
 				+ " ApplicationContext. To display the conditions report re-run"
 				+ " your application with 'debug' enabled.");

spring-boot-project/spring-boot-cli/src/test/java/org/springframework/boot/cli/GrabCommandIntegrationTests.java

 /*
- * Copyright 2012-2017 the original author or authors.
+ * Copyright 2012-2019 the original author or authors.
  *
  * Licensed under the Apache License, Version 2.0 (the "License");
  * you may not use this file except in compliance with the License.
@@ -27,7 +27,7 @@ import org.springframework.boot.cli.command.grab.GrabCommand;
 import org.springframework.util.FileSystemUtils;
 
 import static org.assertj.core.api.Assertions.assertThat;
-import static org.junit.Assert.fail;
+import static org.assertj.core.api.Assertions.assertThatExceptionOfType;
 
 /**
  * Integration tests for {@link GrabCommand}
@@ -64,14 +64,10 @@ public class GrabCommandIntegrationTests {
 
 	@Test
 	public void duplicateDependencyManagementBomAnnotationsProducesAnError() {
-		try {
-			this.cli.grab("duplicateDependencyManagementBom.groovy");
-			fail();
-		}
-		catch (Exception ex) {
-			assertThat(ex.getMessage())
-					.contains("Duplicate @DependencyManagementBom annotation");
-		}
+		assertThatExceptionOfType(Exception.class)
+				.isThrownBy(
+						() -> this.cli.grab("duplicateDependencyManagementBom.groovy"))
+				.withMessageContaining("Duplicate @DependencyManagementBom annotation");
 	}
 
 	@Test

spring-boot-project/spring-boot-devtools/src/test/java/org/springframework/boot/devtools/tunnel/server/SocketTargetServerConnectionTests.java

 /*
- * Copyright 2012-2018 the original author or authors.
+ * Copyright 2012-2019 the original author or authors.
  *
  * Licensed under the Apache License, Version 2.0 (the "License");
  * you may not use this file except in compliance with the License.
@@ -28,7 +28,7 @@ import org.junit.Before;
 import org.junit.Test;
 
 import static org.assertj.core.api.Assertions.assertThat;
-import static org.junit.Assert.fail;
+import static org.assertj.core.api.Assertions.assertThatExceptionOfType;
 
 /**
  * Tests for {@link SocketTargetServerConnection}.
@@ -75,16 +75,13 @@ public class SocketTargetServerConnectionTests {
 		this.server.start();
 		ByteChannel channel = this.connection.open(10);
 		long startTime = System.currentTimeMillis();
-		try {
-			channel.read(ByteBuffer.allocate(5));
-			fail("No socket timeout thrown");
-		}
-		catch (SocketTimeoutException ex) {
-			// Expected
-			long runTime = System.currentTimeMillis() - startTime;
-			assertThat(runTime).isGreaterThanOrEqualTo(10L);
-			assertThat(runTime).isLessThan(10000L);
-		}
+		assertThatExceptionOfType(SocketTimeoutException.class)
+				.isThrownBy(() -> channel.read(ByteBuffer.allocate(5)))
+				.satisfies((ex) -> {
+					long runTime = System.currentTimeMillis() - startTime;
+					assertThat(runTime).isGreaterThanOrEqualTo(10L);
+					assertThat(runTime).isLessThan(10000L);
+				});
 	}
 
 	private static class MockServer {
@@ -162,7 +159,7 @@ public class SocketTargetServerConnectionTests {
 					channel.close();
 				}
 				catch (Exception ex) {
-					fail();
+					throw new RuntimeException(ex);
 				}
 			}
 

spring-boot-project/spring-boot-test-autoconfigure/src/test/java/org/springframework/boot/test/autoconfigure/web/servlet/mockmvc/WebMvcTestWebDriverIntegrationTests.java

 /*
- * Copyright 2012-2018 the original author or authors.
+ * Copyright 2012-2019 the original author or authors.
  *
  * Licensed under the Apache License, Version 2.0 (the "License");
  * you may not use this file except in compliance with the License.
@@ -31,7 +31,7 @@ import org.springframework.security.test.context.support.WithMockUser;
 import org.springframework.test.context.junit4.SpringRunner;
 
 import static org.assertj.core.api.Assertions.assertThat;
-import static org.junit.Assert.fail;
+import static org.assertj.core.api.Assertions.assertThatExceptionOfType;
 
 /**
  * Tests for {@link WebMvcTest} with {@link WebDriver}.
@@ -62,13 +62,8 @@ public class WebMvcTestWebDriverIntegrationTests {
 		this.webDriver.get("/html");
 		WebElement element = this.webDriver.findElement(By.tagName("body"));
 		assertThat(element.getText()).isEqualTo("Hello");
-		try {
-			previousWebDriver.getWindowHandle();
-			fail("Did not call quit()");
-		}
-		catch (NoSuchWindowException ex) {
-			// Expected
-		}
+		assertThatExceptionOfType(NoSuchWindowException.class)
+				.isThrownBy(previousWebDriver::getWindowHandle);
 		assertThat(previousWebDriver).isNotNull().isNotSameAs(this.webDriver);
 	}
 

spring-boot-project/spring-boot-test/src/test/java/org/springframework/boot/test/context/runner/AbstractApplicationContextRunnerTests.java

 /*
- * Copyright 2012-2018 the original author or authors.
+ * Copyright 2012-2019 the original author or authors.
  *
  * Licensed under the Apache License, Version 2.0 (the "License");
  * you may not use this file except in compliance with the License.
@@ -37,8 +37,8 @@ import org.springframework.core.type.AnnotatedTypeMetadata;
 import org.springframework.util.ClassUtils;
 
 import static org.assertj.core.api.Assertions.assertThat;
+import static org.assertj.core.api.Assertions.assertThatExceptionOfType;
 import static org.assertj.core.api.Assertions.assertThatIOException;
-import static org.junit.Assert.fail;
 
 /**
  * Abstract tests for {@link AbstractApplicationContextRunner} implementations.
@@ -153,14 +153,11 @@ public abstract class AbstractApplicationContextRunnerTests<T extends AbstractAp
 	public void runWithClassLoaderShouldSetClassLoaderOnContext() {
 		get().withClassLoader(new FilteredClassLoader(Gson.class.getPackage().getName()))
 				.run((context) -> {
-					try {
-						ClassUtils.forName(Gson.class.getName(),
-								context.getClassLoader());
-						fail("Should have thrown a ClassNotFoundException");
-					}
-					catch (ClassNotFoundException ex) {
-						// expected
-					}
+					assertThatExceptionOfType(ClassNotFoundException.class)
+							.isThrownBy(() -> {
+								ClassUtils.forName(Gson.class.getName(),
+										context.getClassLoader());
+							});
 				});
 	}
 

spring-boot-project/spring-boot/src/test/java/org/springframework/boot/SpringApplicationTests.java

 /*
- * Copyright 2012-2018 the original author or authors.
+ * Copyright 2012-2019 the original author or authors.
  *
  * Licensed under the Apache License, Version 2.0 (the "License");
  * you may not use this file except in compliance with the License.
@@ -107,7 +107,6 @@ import static org.assertj.core.api.Assertions.assertThat;
 import static org.assertj.core.api.Assertions.assertThatExceptionOfType;
 import static org.assertj.core.api.Assertions.assertThatIllegalArgumentException;
 import static org.assertj.core.api.Assertions.assertThatIllegalStateException;
-import static org.junit.Assert.fail;
 import static org.mockito.ArgumentMatchers.isA;
 import static org.mockito.BDDMockito.willThrow;
 import static org.mockito.Mockito.atLeastOnce;
@@ -770,17 +769,11 @@ public class SpringApplicationTests {
 		ExitStatusException failure = new ExitStatusException();
 		willThrow(failure).given(listener)
 				.onApplicationEvent(isA(ApplicationReadyEvent.class));
-		try {
-			application.run();
-			fail("Run should have failed with a RuntimeException");
-		}
-		catch (RuntimeException ex) {
-			verify(listener).onApplicationEvent(isA(ApplicationReadyEvent.class));
-			verify(listener, never())
-					.onApplicationEvent(isA(ApplicationFailedEvent.class));
-			assertThat(exitCodeListener.getExitCode()).isEqualTo(11);
-			assertThat(this.output.toString()).contains("Application run failed");
-		}
+		assertThatExceptionOfType(RuntimeException.class).isThrownBy(application::run);
+		verify(listener).onApplicationEvent(isA(ApplicationReadyEvent.class));
+		verify(listener, never()).onApplicationEvent(isA(ApplicationFailedEvent.class));
+		assertThat(exitCodeListener.getExitCode()).isEqualTo(11);
+		assertThat(this.output.toString()).contains("Application run failed");
 	}
 
 	@Test
@@ -855,12 +848,7 @@ public class SpringApplicationTests {
 		ExitCodeListener listener = new ExitCodeListener();
 		application.addListeners(listener);
 		application.setWebApplicationType(WebApplicationType.NONE);
-		try {
-			application.run();
-			fail("Did not throw");
-		}
-		catch (IllegalStateException ex) {
-		}
+		assertThatIllegalStateException().isThrownBy(application::run);
 		verify(handler).registerExitCode(11);
 		assertThat(listener.getExitCode()).isEqualTo(11);
 	}
@@ -880,12 +868,7 @@ public class SpringApplicationTests {
 		ExitCodeListener listener = new ExitCodeListener();
 		application.addListeners(listener);
 		application.setWebApplicationType(WebApplicationType.NONE);
-		try {
-			application.run();
-			fail("Did not throw");
-		}
-		catch (IllegalStateException ex) {
-		}
+		assertThatIllegalStateException().isThrownBy(application::run);
 		verify(handler).registerExitCode(11);
 		assertThat(listener.getExitCode()).isEqualTo(11);
 	}
@@ -905,12 +888,7 @@ public class SpringApplicationTests {
 		ExitCodeListener listener = new ExitCodeListener();
 		application.addListeners(listener);
 		application.setWebApplicationType(WebApplicationType.NONE);
-		try {
-			application.run();
-			fail("Did not throw");
-		}
-		catch (RuntimeException ex) {
-		}
+		assertThatExceptionOfType(RuntimeException.class).isThrownBy(application::run);
 		ArgumentCaptor<RuntimeException> exceptionCaptor = ArgumentCaptor
 				.forClass(RuntimeException.class);
 		verify(handler).registerLoggedException(exceptionCaptor.capture());
@@ -998,16 +976,12 @@ public class SpringApplicationTests {
 		ApplicationListener<ApplicationEvent> listener = mock(ApplicationListener.class);
 		SpringApplication application = new SpringApplication(ExampleConfig.class);
 		application.addListeners(listener);
-		try {
-			application.run();
-			fail("Run should have failed with an ApplicationContextException");
-		}
-		catch (ApplicationContextException ex) {
-			verifyListenerEvents(listener, ApplicationStartingEvent.class,
-					ApplicationEnvironmentPreparedEvent.class,
-					ApplicationContextInitializedEvent.class,
-					ApplicationPreparedEvent.class, ApplicationFailedEvent.class);
-		}
+		assertThatExceptionOfType(ApplicationContextException.class)
+				.isThrownBy(application::run);
+		verifyListenerEvents(listener, ApplicationStartingEvent.class,
+				ApplicationEnvironmentPreparedEvent.class,
+				ApplicationContextInitializedEvent.class, ApplicationPreparedEvent.class,
+				ApplicationFailedEvent.class);
 	}
 
 	@SuppressWarnings("unchecked")
@@ -1018,16 +992,12 @@ public class SpringApplicationTests {
 				BrokenPostConstructConfig.class);
 		application.setWebApplicationType(WebApplicationType.NONE);
 		application.addListeners(listener);
-		try {
-			application.run();
-			fail("Run should have failed with a BeanCreationException");
-		}
-		catch (BeanCreationException ex) {
-			verifyListenerEvents(listener, ApplicationStartingEvent.class,
-					ApplicationEnvironmentPreparedEvent.class,
-					ApplicationContextInitializedEvent.class,
-					ApplicationPreparedEvent.class, ApplicationFailedEvent.class);
-		}
+		assertThatExceptionOfType(BeanCreationException.class)
+				.isThrownBy(application::run);
+		verifyListenerEvents(listener, ApplicationStartingEvent.class,
+				ApplicationEnvironmentPreparedEvent.class,
+				ApplicationContextInitializedEvent.class, ApplicationPreparedEvent.class,
+				ApplicationFailedEvent.class);
 	}
 
 	@SuppressWarnings("unchecked")
@@ -1038,13 +1008,9 @@ public class SpringApplicationTests {
 		SpringApplication application = new SpringApplication(ExampleConfig.class);
 		application.addInitializers((applicationContext) -> applicationContext
 				.addApplicationListener(listener));
-		try {
-			application.run();
-			fail("Run should have failed with an ApplicationContextException");
-		}
-		catch (ApplicationContextException ex) {
-			verifyListenerEvents(listener, ApplicationFailedEvent.class);
-		}
+		assertThatExceptionOfType(ApplicationContextException.class)
+				.isThrownBy(application::run);
+		verifyListenerEvents(listener, ApplicationFailedEvent.class);
 	}
 
 	@SuppressWarnings("unchecked")
@@ -1056,13 +1022,9 @@ public class SpringApplicationTests {
 		application.setWebApplicationType(WebApplicationType.NONE);
 		application.addInitializers((applicationContext) -> applicationContext
 				.addApplicationListener(listener));
-		try {
-			application.run();
-			fail("Run should have failed with a BeanCreationException");
-		}
-		catch (BeanCreationException ex) {
-			verifyListenerEvents(listener, ApplicationFailedEvent.class);
-		}
+		assertThatExceptionOfType(BeanCreationException.class)
+				.isThrownBy(application::run);
+		verifyListenerEvents(listener, ApplicationFailedEvent.class);
 	}
 
 	@Test

spring-boot-project/spring-boot/src/test/java/org/springframework/boot/context/properties/ConfigurationPropertiesTests.java

 /*
- * Copyright 2012-2018 the original author or authors.
+ * Copyright 2012-2019 the original author or authors.
  *
  * Licensed under the Apache License, Version 2.0 (the "License");
  * you may not use this file except in compliance with the License.
@@ -82,7 +82,6 @@ import static org.assertj.core.api.Assertions.assertThat;
 import static org.assertj.core.api.Assertions.assertThatExceptionOfType;
 import static org.assertj.core.api.Assertions.assertThatIllegalArgumentException;
 import static org.assertj.core.api.Assertions.entry;
-import static org.junit.Assert.fail;
 import static org.mockito.ArgumentMatchers.any;
 import static org.mockito.ArgumentMatchers.anyString;
 import static org.mockito.ArgumentMatchers.eq;
@@ -702,15 +701,13 @@ public class ConfigurationPropertiesTests {
 
 	@Test
 	public void loadWhenHasConfigurationPropertiesValidatorShouldApplyValidator() {
-		try {
-			load(WithCustomValidatorConfiguration.class);
-			fail("Did not throw");
-		}
-		catch (Exception ex) {
-			assertThat(ex).hasCauseInstanceOf(BindException.class);
-			assertThat(ex.getCause())
-					.hasCauseExactlyInstanceOf(BindValidationException.class);
-		}
+		assertThatExceptionOfType(Exception.class)
+				.isThrownBy(() -> load(WithCustomValidatorConfiguration.class))
+				.satisfies((ex) -> {
+					assertThat(ex).hasCauseInstanceOf(BindException.class);
+					assertThat(ex.getCause())
+							.hasCauseExactlyInstanceOf(BindValidationException.class);
+				});
 	}
 
 	@Test
@@ -723,15 +720,12 @@ public class ConfigurationPropertiesTests {
 
 	@Test
 	public void loadWhenConfigurationPropertiesIsAlsoValidatorShouldApplyValidator() {
-		try {
-			load(ValidatorProperties.class);
-			fail("Did not throw");
-		}
-		catch (Exception ex) {
-			assertThat(ex).hasCauseInstanceOf(BindException.class);
-			assertThat(ex.getCause())
-					.hasCauseExactlyInstanceOf(BindValidationException.class);
-		}
+		assertThatExceptionOfType(Exception.class)
+				.isThrownBy(() -> load(ValidatorProperties.class)).satisfies((ex) -> {
+					assertThat(ex).hasCauseInstanceOf(BindException.class);
+					assertThat(ex.getCause())
+							.hasCauseExactlyInstanceOf(BindValidationException.class);
+				});
 	}
 
 	@Test

spring-boot-project/spring-boot/src/test/java/org/springframework/boot/context/properties/bind/ArrayBinderTests.java

 /*
- * Copyright 2012-2018 the original author or authors.
+ * Copyright 2012-2019 the original author or authors.
  *
  * Licensed under the Apache License, Version 2.0 (the "License");
  * you may not use this file except in compliance with the License.
@@ -32,7 +32,7 @@ import org.springframework.boot.context.properties.source.MockConfigurationPrope
 import org.springframework.core.ResolvableType;
 
 import static org.assertj.core.api.Assertions.assertThat;
-import static org.assertj.core.api.Assertions.fail;
+import static org.assertj.core.api.Assertions.assertThatExceptionOfType;
 import static org.mockito.ArgumentMatchers.any;
 import static org.mockito.ArgumentMatchers.eq;
 import static org.mockito.ArgumentMatchers.isA;
@@ -145,18 +145,16 @@ public class ArrayBinderTests {
 		source.put("foo[1]", "1");
 		source.put("foo[3]", "3");
 		this.sources.add(source);
-		try {
-			this.binder.bind("foo", INTEGER_ARRAY);
-			fail("No exception thrown");
-		}
-		catch (BindException ex) {
-			Set<ConfigurationProperty> unbound = ((UnboundConfigurationPropertiesException) ex
-					.getCause()).getUnboundProperties();
-			assertThat(unbound.size()).isEqualTo(1);
-			ConfigurationProperty property = unbound.iterator().next();
-			assertThat(property.getName().toString()).isEqualTo("foo[3]");
-			assertThat(property.getValue()).isEqualTo("3");
-		}
+		assertThatExceptionOfType(BindException.class)
+				.isThrownBy(() -> this.binder.bind("foo", INTEGER_ARRAY))
+				.satisfies((ex) -> {
+					Set<ConfigurationProperty> unbound = ((UnboundConfigurationPropertiesException) ex
+							.getCause()).getUnboundProperties();
+					assertThat(unbound.size()).isEqualTo(1);
+					ConfigurationProperty property = unbound.iterator().next();
+					assertThat(property.getName().toString()).isEqualTo("foo[3]");
+					assertThat(property.getValue()).isEqualTo("3");
+				});
 	}
 
 	@Test

spring-boot-project/spring-boot/src/test/java/org/springframework/boot/context/properties/bind/CollectionBinderTests.java

@@ -38,7 +38,7 @@ import org.springframework.core.env.StandardEnvironment;
 import org.springframework.test.context.support.TestPropertySourceUtils;
 
 import static org.assertj.core.api.Assertions.assertThat;
-import static org.assertj.core.api.Assertions.fail;
+import static org.assertj.core.api.Assertions.assertThatExceptionOfType;
 
 /**
  * Tests for {@link CollectionBinder}.
@@ -121,18 +121,16 @@ public class CollectionBinderTests {
 		source.put("foo[1]", "1");
 		source.put("foo[3]", "3");
 		this.sources.add(source);
-		try {
-			this.binder.bind("foo", INTEGER_LIST);
-			fail("No exception thrown");
-		}
-		catch (BindException ex) {
-			Set<ConfigurationProperty> unbound = ((UnboundConfigurationPropertiesException) ex
-					.getCause()).getUnboundProperties();
-			assertThat(unbound).hasSize(1);
-			ConfigurationProperty property = unbound.iterator().next();
-			assertThat(property.getName().toString()).isEqualTo("foo[3]");
-			assertThat(property.getValue()).isEqualTo("3");
-		}
+		assertThatExceptionOfType(BindException.class)
+				.isThrownBy(() -> this.binder.bind("foo", INTEGER_LIST))
+				.satisfies((ex) -> {
+					Set<ConfigurationProperty> unbound = ((UnboundConfigurationPropertiesException) ex
+							.getCause()).getUnboundProperties();
+					assertThat(unbound).hasSize(1);
+					ConfigurationProperty property = unbound.iterator().next();
+					assertThat(property.getName().toString()).isEqualTo("foo[3]");
+					assertThat(property.getValue()).isEqualTo("3");
+				});
 	}
 
 	@Test
@@ -142,19 +140,16 @@ public class CollectionBinderTests {
 		source.put("foo[1].value", "2");
 		source.put("foo[4].value", "4");
 		this.sources.add(source);
-		try {
-			Bindable<List<JavaBean>> target = Bindable.listOf(JavaBean.class);
-			this.binder.bind("foo", target);
-			fail("No exception thrown");
-		}
-		catch (BindException ex) {
-			Set<ConfigurationProperty> unbound = ((UnboundConfigurationPropertiesException) ex
-					.getCause()).getUnboundProperties();
-			assertThat(unbound).hasSize(1);
-			ConfigurationProperty property = unbound.iterator().next();
-			assertThat(property.getName().toString()).isEqualTo("foo[4].value");
-			assertThat(property.getValue()).isEqualTo("4");
-		}
+		Bindable<List<JavaBean>> target = Bindable.listOf(JavaBean.class);
+		assertThatExceptionOfType(BindException.class)
+				.isThrownBy(() -> this.binder.bind("foo", target)).satisfies((ex) -> {
+					Set<ConfigurationProperty> unbound = ((UnboundConfigurationPropertiesException) ex
+							.getCause()).getUnboundProperties();
+					assertThat(unbound).hasSize(1);
+					ConfigurationProperty property = unbound.iterator().next();
+					assertThat(property.getName().toString()).isEqualTo("foo[4].value");
+					assertThat(property.getValue()).isEqualTo("4");
+				});
 	}
 
 	@Test

spring-boot-project/spring-boot/src/test/java/org/springframework/boot/context/properties/bind/handler/NoUnboundElementsBindHandlerTests.java

 /*
- * Copyright 2012-2017 the original author or authors.
+ * Copyright 2012-2019 the original author or authors.
  *
  * Licensed under the Apache License, Version 2.0 (the "License");
  * you may not use this file except in compliance with the License.
@@ -30,7 +30,7 @@ import org.springframework.boot.context.properties.source.ConfigurationPropertyS
 import org.springframework.boot.context.properties.source.MockConfigurationPropertySource;
 
 import static org.assertj.core.api.Assertions.assertThat;
-import static org.assertj.core.api.Assertions.fail;
+import static org.assertj.core.api.Assertions.assertThatExceptionOfType;
 
 /**
  * Tests for {@link NoUnboundElementsBindHandler}.
@@ -75,15 +75,11 @@ public class NoUnboundElementsBindHandlerTests {
 		source.put("example.baz", "bar");
 		this.sources.add(source);
 		this.binder = new Binder(this.sources);
-		try {
-			this.binder.bind("example", Bindable.of(Example.class),
-					new NoUnboundElementsBindHandler());
-			fail("did not throw");
-		}
-		catch (BindException ex) {
-			assertThat(ex.getCause().getMessage())
-					.contains("The elements [example.baz] were left unbound");
-		}
+		assertThatExceptionOfType(BindException.class)
+				.isThrownBy(() -> this.binder.bind("example", Bindable.of(Example.class),
+						new NoUnboundElementsBindHandler()))
+				.satisfies((ex) -> assertThat(ex.getCause().getMessage())
+						.contains("The elements [example.baz] were left unbound"));
 	}
 
 	@Test

spring-boot-project/spring-boot/src/test/java/org/springframework/boot/context/properties/source/ConfigurationPropertyNameTests.java

 /*
- * Copyright 2012-2018 the original author or authors.
+ * Copyright 2012-2019 the original author or authors.
  *
  * Licensed under the Apache License, Version 2.0 (the "License");
  * you may not use this file except in compliance with the License.
@@ -28,7 +28,6 @@ import org.springframework.boot.context.properties.source.ConfigurationPropertyN
 import static org.assertj.core.api.Assertions.assertThat;
 import static org.assertj.core.api.Assertions.assertThatExceptionOfType;
 import static org.assertj.core.api.Assertions.assertThatIllegalArgumentException;
-import static org.assertj.core.api.Assertions.fail;
 
 /**
  * Tests for {@link ConfigurationPropertyName}.
@@ -78,13 +77,9 @@ public class ConfigurationPropertyNameTests {
 	public void ofNameShouldNotContainInvalidChars() {
 		String invalid = "_@$%*+=':;";
 		for (char c : invalid.toCharArray()) {
-			try {
-				ConfigurationPropertyName.of("foo" + c);
-				fail("Did not throw for invalid char " + c);
-			}
-			catch (InvalidConfigurationPropertyNameException ex) {
-				assertThat(ex.getMessage()).contains("is not valid");
-			}
+			assertThatExceptionOfType(InvalidConfigurationPropertyNameException.class)
+					.isThrownBy(() -> ConfigurationPropertyName.of("foo" + c)).satisfies(
+							(ex) -> assertThat(ex.getMessage()).contains("is not valid"));
 		}
 	}
 

spring-boot-project/spring-boot/src/test/java/org/springframework/boot/convert/DurationStyleTests.java

 /*
- * Copyright 2012-2018 the original author or authors.
+ * Copyright 2012-2019 the original author or authors.
  *
  * Licensed under the Apache License, Version 2.0 (the "License");
  * you may not use this file except in compliance with the License.
@@ -23,7 +23,6 @@ import org.junit.Test;
 
 import static org.assertj.core.api.Assertions.assertThat;
 import static org.assertj.core.api.Assertions.assertThatIllegalArgumentException;
-import static org.junit.Assert.fail;
 
 /**
  * Tests for {@link DurationStyle}.
@@ -243,13 +242,10 @@ public class DurationStyleTests {
 
 	@Test
 	public void parseSimpleWhenUnknownUnitShouldThrowException() {
-		try {
-			DurationStyle.SIMPLE.parse("10mb");
-			fail("Did not throw");
-		}
-		catch (IllegalArgumentException ex) {
-			assertThat(ex.getCause().getMessage()).isEqualTo("Unknown unit 'mb'");
-		}
+		assertThatIllegalArgumentException()
+				.isThrownBy(() -> DurationStyle.SIMPLE.parse("10mb"))
+				.satisfies((ex) -> assertThat(ex.getCause().getMessage())
+						.isEqualTo("Unknown unit 'mb'"));
 	}
 
 	@Test

spring-boot-project/spring-boot/src/test/java/org/springframework/boot/diagnostics/FailureAnalyzersIntegrationTests.java

 /*
- * Copyright 2012-2017 the original author or authors.
+ * Copyright 2012-2019 the original author or authors.
  *
  * Licensed under the Apache License, Version 2.0 (the "License");
  * you may not use this file except in compliance with the License.
@@ -28,7 +28,7 @@ import org.springframework.boot.web.server.PortInUseException;
 import org.springframework.context.annotation.Configuration;
 
 import static org.assertj.core.api.Assertions.assertThat;
-import static org.junit.Assert.fail;
+import static org.assertj.core.api.Assertions.assertThatExceptionOfType;
 
 /**
  * Integration tests for {@link FailureAnalyzers}.
@@ -42,15 +42,10 @@ public class FailureAnalyzersIntegrationTests {
 
 	@Test
 	public void analysisIsPerformed() {
-		try {
-			new SpringApplicationBuilder(TestConfiguration.class)
-					.web(WebApplicationType.NONE).run();
-			fail("Application started successfully");
-		}
-		catch (Exception ex) {
-			assertThat(this.outputCapture.toString())
-					.contains("APPLICATION FAILED TO START");
-		}
+		assertThatExceptionOfType(Exception.class)
+				.isThrownBy(() -> new SpringApplicationBuilder(TestConfiguration.class)
+						.web(WebApplicationType.NONE).run());
+		assertThat(this.outputCapture.toString()).contains("APPLICATION FAILED TO START");
 	}
 
 	@Configuration

spring-boot-project/spring-boot/src/test/java/org/springframework/boot/diagnostics/analyzer/ValidationExceptionFailureAnalyzerTests.java

 /*
- * Copyright 2012-2018 the original author or authors.
+ * Copyright 2012-2019 the original author or authors.
  *
  * Licensed under the Apache License, Version 2.0 (the "License");
  * you may not use this file except in compliance with the License.
@@ -21,14 +21,13 @@ import org.junit.runner.RunWith;
 
 import org.springframework.boot.context.properties.ConfigurationProperties;
 import org.springframework.boot.context.properties.EnableConfigurationProperties;
-import org.springframework.boot.diagnostics.FailureAnalysis;
 import org.springframework.boot.testsupport.runner.classpath.ClassPathExclusions;
 import org.springframework.boot.testsupport.runner.classpath.ModifiedClassPathRunner;
 import org.springframework.context.annotation.AnnotationConfigApplicationContext;
 import org.springframework.validation.annotation.Validated;
 
 import static org.assertj.core.api.Assertions.assertThat;
-import static org.junit.Assert.fail;
+import static org.assertj.core.api.Assertions.assertThatExceptionOfType;
 
 /**
  * Tests for {@link ValidationExceptionFailureAnalyzer}
@@ -41,15 +40,12 @@ public class ValidationExceptionFailureAnalyzerTests {
 
 	@Test
 	public void validatedPropertiesTest() {
-		try {
-			new AnnotationConfigApplicationContext(TestConfiguration.class).close();
-			fail("Expected failure did not occur");
-		}
-		catch (Exception ex) {
-			FailureAnalysis analysis = new ValidationExceptionFailureAnalyzer()
-					.analyze(ex);
-			assertThat(analysis).isNotNull();
-		}
+		assertThatExceptionOfType(Exception.class)
+				.isThrownBy(() -> new AnnotationConfigApplicationContext(
+						TestConfiguration.class).close())
+				.satisfies((ex) -> assertThat(
+						new ValidationExceptionFailureAnalyzer().analyze(ex))
+								.isNotNull());
 	}
 
 	@Test

spring-boot-project/spring-boot/src/test/java/org/springframework/boot/web/embedded/jetty/SslServerCustomizerTests.java

@@ -34,6 +34,7 @@ import org.springframework.boot.web.server.Ssl;
 import org.springframework.boot.web.server.WebServerException;
 
 import static org.assertj.core.api.Assertions.assertThat;
+import static org.assertj.core.api.Assertions.assertThatExceptionOfType;
 
 /**
  * Tests for {@link SslServerCustomizer}.
@@ -85,13 +86,14 @@ public class SslServerCustomizerTests {
 			throws Exception {
 		Ssl ssl = new Ssl();
 		SslServerCustomizer customizer = new SslServerCustomizer(null, ssl, null, null);
-		try {
-			customizer.configureSsl(new SslContextFactory(), ssl, null);
-		}
-		catch (Exception ex) {
-			assertThat(ex).isInstanceOf(WebServerException.class);
-			assertThat(ex).hasMessageContaining("Could not load key store 'null'");
-		}
+		assertThatExceptionOfType(Exception.class)
+				.isThrownBy(
+						() -> customizer.configureSsl(new SslContextFactory(), ssl, null))
+				.satisfies((ex) -> {
+					assertThat(ex).isInstanceOf(WebServerException.class);
+					assertThat(ex)
+							.hasMessageContaining("Could not load key store 'null'");
+				});
 	}
 
 	private Server createCustomizedServer() {

spring-boot-project/spring-boot/src/test/java/org/springframework/boot/web/embedded/netty/SslServerCustomizerTests.java

@@ -23,8 +23,7 @@ import org.junit.Test;
 import org.springframework.boot.web.server.Ssl;
 import org.springframework.boot.web.server.WebServerException;
 
-import static org.assertj.core.api.Assertions.assertThat;
-import static org.junit.Assert.fail;
+import static org.assertj.core.api.Assertions.assertThatIllegalStateException;
 
 /**
  * Tests for {@link SslServerCustomizer}.
@@ -41,15 +40,10 @@ public class SslServerCustomizerTests {
 		ssl.setKeyStore("src/test/resources/test.jks");
 		ssl.setKeyStoreProvider("com.example.KeyStoreProvider");
 		SslServerCustomizer customizer = new SslServerCustomizer(ssl, null, null);
-		try {
-			customizer.getKeyManagerFactory(ssl, null);
-			fail();
-		}
-		catch (IllegalStateException ex) {
-			Throwable cause = ex.getCause();
-			assertThat(cause).isInstanceOf(NoSuchProviderException.class);
-			assertThat(cause).hasMessageContaining("com.example.KeyStoreProvider");
-		}
+		assertThatIllegalStateException()
+				.isThrownBy(() -> customizer.getKeyManagerFactory(ssl, null))
+				.withCauseInstanceOf(NoSuchProviderException.class)
+				.withMessageContaining("com.example.KeyStoreProvider");
 	}
 
 	@Test
@@ -59,15 +53,10 @@ public class SslServerCustomizerTests {
 		ssl.setTrustStore("src/test/resources/test.jks");
 		ssl.setTrustStoreProvider("com.example.TrustStoreProvider");
 		SslServerCustomizer customizer = new SslServerCustomizer(ssl, null, null);
-		try {
-			customizer.getTrustManagerFactory(ssl, null);
-			fail();
-		}
-		catch (IllegalStateException ex) {
-			Throwable cause = ex.getCause();
-			assertThat(cause).isInstanceOf(NoSuchProviderException.class);
-			assertThat(cause).hasMessageContaining("com.example.TrustStoreProvider");
-		}
+		assertThatIllegalStateException()
+				.isThrownBy(() -> customizer.getTrustManagerFactory(ssl, null))
+				.withCauseInstanceOf(NoSuchProviderException.class)
+				.withMessageContaining("com.example.TrustStoreProvider");
 	}
 
 	@Test
@@ -75,15 +64,10 @@ public class SslServerCustomizerTests {
 			throws Exception {
 		Ssl ssl = new Ssl();
 		SslServerCustomizer customizer = new SslServerCustomizer(ssl, null, null);
-		try {
-			customizer.getKeyManagerFactory(ssl, null);
-			fail();
-		}
-		catch (IllegalStateException ex) {
-			Throwable cause = ex.getCause();
-			assertThat(cause).isInstanceOf(WebServerException.class);
-			assertThat(cause).hasMessageContaining("Could not load key store 'null'");
-		}
+		assertThatIllegalStateException()
+				.isThrownBy(() -> customizer.getKeyManagerFactory(ssl, null))
+				.withCauseInstanceOf(WebServerException.class)
+				.withMessageContaining("Could not load key store 'null'");
 	}
 
 }

spring-boot-project/spring-boot/src/test/java/org/springframework/boot/web/embedded/tomcat/SslConnectorCustomizerTests.java

@@ -43,7 +43,7 @@ import org.springframework.core.io.Resource;
 import org.springframework.test.util.ReflectionTestUtils;
 
 import static org.assertj.core.api.Assertions.assertThat;
-import static org.junit.Assert.fail;
+import static org.assertj.core.api.Assertions.assertThatExceptionOfType;
 import static org.mockito.BDDMockito.given;
 import static org.mockito.Mockito.mock;
 
@@ -193,15 +193,10 @@ public class SslConnectorCustomizerTests {
 
 	@Test
 	public void customizeWhenSslIsEnabledWithNoKeyStoreThrowsWebServerException() {
-		try {
-			new SslConnectorCustomizer(new Ssl(), null)
-					.customize(this.tomcat.getConnector());
-			fail();
-		}
-		catch (Exception ex) {
-			assertThat(ex).isInstanceOf(WebServerException.class);
-			assertThat(ex).hasMessageContaining("Could not load key store 'null'");
-		}
+		assertThatExceptionOfType(WebServerException.class)
+				.isThrownBy(() -> new SslConnectorCustomizer(new Ssl(), null)
+						.customize(this.tomcat.getConnector()))
+				.withMessageContaining("Could not load key store 'null'");
 	}
 
 	private KeyStore loadStore() throws KeyStoreException, IOException,

spring-boot-project/spring-boot/src/test/java/org/springframework/boot/web/embedded/tomcat/TomcatServletWebServerFactoryTests.java

@@ -65,7 +65,6 @@ import org.springframework.test.util.ReflectionTestUtils;
 import static org.assertj.core.api.Assertions.assertThat;
 import static org.assertj.core.api.Assertions.assertThatExceptionOfType;
 import static org.assertj.core.api.Assertions.assertThatIllegalArgumentException;
-import static org.junit.Assert.fail;
 import static org.mockito.ArgumentMatchers.any;
 import static org.mockito.Mockito.inOrder;
 import static org.mockito.Mockito.mock;
@@ -277,19 +276,14 @@ public class TomcatServletWebServerFactoryTests
 	}
 
 	@Test
-	public void primaryConnectorPortClashThrowsIllegalStateException()
-			throws IOException {
+	public void primaryConnectorPortClashThrowsWebServerException() throws IOException {
 		doWithBlockedPort((port) -> {
 			TomcatServletWebServerFactory factory = getFactory();
 			factory.setPort(port);
-			try {
+			assertThatExceptionOfType(WebServerException.class).isThrownBy(() -> {
 				this.webServer = factory.getWebServer();
 				this.webServer.start();
-				fail();
-			}
-			catch (WebServerException ex) {
-				// Ignore
-			}
+			});
 		});
 	}
 

spring-boot-project/spring-boot/src/test/java/org/springframework/boot/web/embedded/undertow/SslBuilderCustomizerTests.java

@@ -28,7 +28,7 @@ import org.springframework.boot.web.server.WebServerException;
 import org.springframework.test.util.ReflectionTestUtils;
 
 import static org.assertj.core.api.Assertions.assertThat;
-import static org.junit.Assert.fail;
+import static org.assertj.core.api.Assertions.assertThatIllegalStateException;
 
 /**
  * Tests for {@link SslBuilderCustomizer}
@@ -60,15 +60,11 @@ public class SslBuilderCustomizerTests {
 		ssl.setKeyStoreProvider("com.example.KeyStoreProvider");
 		SslBuilderCustomizer customizer = new SslBuilderCustomizer(8080,
 				InetAddress.getLocalHost(), ssl, null);
-		try {
-			ReflectionTestUtils.invokeMethod(customizer, "getKeyManagers", ssl, null);
-			fail();
-		}
-		catch (IllegalStateException ex) {
-			Throwable cause = ex.getCause();
-			assertThat(cause).isInstanceOf(NoSuchProviderException.class);
-			assertThat(cause).hasMessageContaining("com.example.KeyStoreProvider");
-		}
+		assertThatIllegalStateException()
+				.isThrownBy(() -> ReflectionTestUtils.invokeMethod(customizer,
+						"getKeyManagers", ssl, null))
+				.withCauseInstanceOf(NoSuchProviderException.class)
+				.withMessageContaining("com.example.KeyStoreProvider");
 	}
 
 	@Test
@@ -79,15 +75,11 @@ public class SslBuilderCustomizerTests {
 		ssl.setTrustStoreProvider("com.example.TrustStoreProvider");
 		SslBuilderCustomizer customizer = new SslBuilderCustomizer(8080,
 				InetAddress.getLocalHost(), ssl, null);
-		try {
-			ReflectionTestUtils.invokeMethod(customizer, "getTrustManagers", ssl, null);
-			fail();
-		}
-		catch (IllegalStateException ex) {
-			Throwable cause = ex.getCause();
-			assertThat(cause).isInstanceOf(NoSuchProviderException.class);
-			assertThat(cause).hasMessageContaining("com.example.TrustStoreProvider");
-		}
+		assertThatIllegalStateException()
+				.isThrownBy(() -> ReflectionTestUtils.invokeMethod(customizer,
+						"getTrustManagers", ssl, null))
+				.withCauseInstanceOf(NoSuchProviderException.class)
+				.withMessageContaining("com.example.TrustStoreProvider");
 	}
 
 	@Test
@@ -96,15 +88,11 @@ public class SslBuilderCustomizerTests {
 		Ssl ssl = new Ssl();
 		SslBuilderCustomizer customizer = new SslBuilderCustomizer(8080,
 				InetAddress.getLocalHost(), ssl, null);
-		try {
-			ReflectionTestUtils.invokeMethod(customizer, "getKeyManagers", ssl, null);
-			fail();
-		}
-		catch (IllegalStateException ex) {
-			Throwable cause = ex.getCause();
-			assertThat(cause).isInstanceOf(WebServerException.class);
-			assertThat(cause).hasMessageContaining("Could not load key store 'null'");
-		}
+		assertThatIllegalStateException()
+				.isThrownBy(() -> ReflectionTestUtils.invokeMethod(customizer,
+						"getKeyManagers", ssl, null))
+				.withCauseInstanceOf(WebServerException.class)
+				.withMessageContaining("Could not load key store 'null'");
 	}
 
 }

spring-boot-project/spring-boot/src/test/java/org/springframework/boot/web/servlet/server/AbstractServletWebServerFactoryTests.java

 /*
- * Copyright 2012-2018 the original author or authors.
+ * Copyright 2012-2019 the original author or authors.
  *
  * Licensed under the Apache License, Version 2.0 (the "License");
  * you may not use this file except in compliance with the License.
@@ -911,17 +911,13 @@ public abstract class AbstractServletWebServerFactoryTests {
 	public void portClashOfPrimaryConnectorResultsInPortInUseException()
 			throws IOException {
 		doWithBlockedPort((port) -> {
-			try {
+			assertThatExceptionOfType(RuntimeException.class).isThrownBy(() -> {
 				AbstractServletWebServerFactory factory = getFactory();
 				factory.setPort(port);
 				AbstractServletWebServerFactoryTests.this.webServer = factory
 						.getWebServer();
 				AbstractServletWebServerFactoryTests.this.webServer.start();
-				fail();
-			}
-			catch (RuntimeException ex) {
-				handleExceptionCausedByBlockedPort(ex, port);
-			}
+			}).satisfies((ex) -> handleExceptionCausedByBlockedPort(ex, port));
 		});
 	}
 
@@ -929,17 +925,13 @@ public abstract class AbstractServletWebServerFactoryTests {
 	public void portClashOfSecondaryConnectorResultsInPortInUseException()
 			throws IOException {
 		doWithBlockedPort((port) -> {
-			try {
+			assertThatExceptionOfType(RuntimeException.class).isThrownBy(() -> {
 				AbstractServletWebServerFactory factory = getFactory();
 				addConnector(port, factory);
 				AbstractServletWebServerFactoryTests.this.webServer = factory
 						.getWebServer();
 				AbstractServletWebServerFactoryTests.this.webServer.start();
-				fail();
-			}
-			catch (RuntimeException ex) {
-				handleExceptionCausedByBlockedPort(ex, port);
-			}
+			}).satisfies((ex) -> handleExceptionCausedByBlockedPort(ex, port));
 		});
 	}