Support Java 14 (#3310)

* Support Java 14

* Provide changes to avoid deprecated Java API
and have a compatibility back to Java 8
* Change affected test classes to JUnit 5 whenever it is possible
* Ignore/Disable some TCP/IP tests which don't pass on Java 14

* Fix (some) TCP tests on JRE 14

* Fix SSL Handshake test - client side handshake is successful with java 14

- change the badClient cert to a badServer cert to force an error on the client side

Co-authored-by: artembilan <raven666>
Co-authored-by: Gary Russell <grussell@pivotal.io>

spring-integration-core/src/main/java/org/springframework/integration/dsl/EndpointSpec.java

@@ -1,5 +1,5 @@
 /*
- * Copyright 2016-2019 the original author or authors.
+ * Copyright 2016-2020 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.
@@ -20,6 +20,7 @@ import java.util.LinkedHashMap;
 import java.util.Map;
 import java.util.function.Function;
 
+import org.springframework.beans.BeanUtils;
 import org.springframework.beans.factory.BeanNameAware;
 import org.springframework.core.ResolvableType;
 import org.springframework.integration.channel.DirectChannel;
@@ -55,14 +56,9 @@ public abstract class EndpointSpec<S extends EndpointSpec<S, F, H>, F extends Be
 
 	@SuppressWarnings("unchecked")
 	protected EndpointSpec(H handler) {
-		try {
-			Class<?> fClass = ResolvableType.forClass(this.getClass()).as(EndpointSpec.class).resolveGenerics()[1];
-			this.endpointFactoryBean = (F) fClass.newInstance();
-			this.handler = handler;
-		}
-		catch (Exception e) {
-			throw new IllegalStateException(e);
-		}
+		Class<?> fClass = ResolvableType.forClass(this.getClass()).as(EndpointSpec.class).resolveGenerics()[1];
+		this.endpointFactoryBean = (F) BeanUtils.instantiateClass(fClass);
+		this.handler = handler;
 	}
 
 	@Override

spring-integration-core/src/main/java/org/springframework/integration/dsl/IntegrationFlowAdapter.java

@@ -179,14 +179,14 @@ public abstract class IntegrationFlowAdapter implements IntegrationFlow, SmartLi
 		return IntegrationFlows.from(inboundGatewaySpec);
 	}
 
-	protected <T> IntegrationFlowBuilder from(Supplier<T> messageSource) {
-		return IntegrationFlows.from(messageSource);
+	protected <T> IntegrationFlowBuilder fromSupplier(Supplier<T> messageSource) {
+		return IntegrationFlows.fromSupplier(messageSource);
 	}
 
-	protected <T> IntegrationFlowBuilder from(Supplier<T> messageSource,
+	protected <T> IntegrationFlowBuilder fromSupplier(Supplier<T> messageSource,
 			Consumer<SourcePollingChannelAdapterSpec> endpointConfigurer) {
 
-		return IntegrationFlows.from(messageSource, endpointConfigurer);
+		return IntegrationFlows.fromSupplier(messageSource, endpointConfigurer);
 	}
 
 	protected IntegrationFlowBuilder from(Class<?> serviceInterface) {

spring-integration-core/src/main/java/org/springframework/integration/dsl/IntegrationFlows.java

@@ -141,8 +141,8 @@ public final class IntegrationFlows {
 	 * @return new {@link IntegrationFlowBuilder}.
 	 * @see Supplier
 	 */
-	public static <T> IntegrationFlowBuilder from(Supplier<T> messageSource) {
-		return from(messageSource, null);
+	public static <T> IntegrationFlowBuilder fromSupplier(Supplier<T> messageSource) {
+		return fromSupplier(messageSource, null);
 	}
 
 	/**
@@ -156,7 +156,7 @@ public final class IntegrationFlows {
 	 * @return new {@link IntegrationFlowBuilder}.
 	 * @see Supplier
 	 */
-	public static <T> IntegrationFlowBuilder from(Supplier<T> messageSource,
+	public static <T> IntegrationFlowBuilder fromSupplier(Supplier<T> messageSource,
 			Consumer<SourcePollingChannelAdapterSpec> endpointConfigurer) {
 
 		Assert.notNull(messageSource, "'messageSource' must not be null");

spring-integration-core/src/main/java/org/springframework/integration/handler/BridgeHandler.java

@@ -1,5 +1,5 @@
 /*
- * Copyright 2002-2019 the original author or authors.
+ * Copyright 2002-2020 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.messaging.Message;
  * <p>
  * The BridgeHandler can be used as a stopper at the end of an assembly line of
  * channels. In this setup the output channel doesn't have to be set, but if the
- * output channel is omitted the <tt>REPLY_CHANNEL</tt> MUST be set on the
+ * output channel is omitted the {@code REPLY_CHANNEL} MUST be set on the
  * message. Otherwise, a MessagingException will be thrown at runtime.
  *
  * @author Mark Fisher

spring-integration-core/src/main/java/org/springframework/integration/metadata/MetadataStore.java

@@ -1,5 +1,5 @@
 /*
- * Copyright 2002-2019 the original author or authors.
+ * Copyright 2002-2020 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.
@@ -52,8 +52,8 @@ public interface MetadataStore {
 	/**
 	 * Remove a value for the given key from this MetadataStore.
 	 * @param key The key.
-	 * @return The previous value associated with <tt>key</tt>, or
-	 *         <tt>null</tt> if there was no mapping for <tt>key</tt>.
+	 * @return The previous value associated with key, or
+	 *         null if there was no mapping for key.
 	 */
 	@ManagedAttribute
 	String remove(String key);

spring-integration-core/src/main/kotlin/org/springframework/integration/dsl/IntegrationFlowDsl.kt

@@ -106,7 +106,7 @@ fun integrationFlow(messageSource: MessageSourceSpec<*, out MessageSource<*>>,
 fun integrationFlow(source: () -> Any,
 					options: SourcePollingChannelAdapterSpec.() -> Unit = {},
 					flow: KotlinIntegrationFlowDefinition.() -> Unit) =
-		buildIntegrationFlow(IntegrationFlows.from(source, options), flow)
+		buildIntegrationFlow(IntegrationFlows.fromSupplier(source, options), flow)
 
 /**
  * Functional [IntegrationFlow] definition in Kotlin DSL for [IntegrationFlows.from] -