Support primary TxMgrs and DataSources in the TCF

Prior to this commit, the transaction manager and data source look-up
algorithms in the Spring TestContext Framework were not capable of
retrieving 'primary' beans of those types, even though 'primary' beans
are supported in production as well as for injecting dependencies into
test instances. Specifically, if there was more than one transaction
manager or data source bean and one of them was flagged as 'primary',
the retrieveTransactionManager() and retrieveDataSource() methods in
TestContextTransactionUtils would simply return null for such beans.

This commit updates TestContextTransactionUtils by adding support for
looking up primary transaction managers and data sources.

Issue: SPR-13891

spring-test/src/test/java/org/springframework/test/context/jdbc/PrimaryDataSourceTests.java

@@ -0,0 +1,89 @@
+/*
+ * Copyright 2002-2016 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.
+ * You may obtain a copy of the License at
+ *
+ *      http://www.apache.org/licenses/LICENSE-2.0
+ *
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
+ */
+
+package org.springframework.test.context.jdbc;
+
+import javax.sql.DataSource;
+
+import org.junit.Test;
+import org.junit.runner.RunWith;
+
+import org.springframework.beans.factory.annotation.Autowired;
+import org.springframework.context.annotation.Bean;
+import org.springframework.context.annotation.Configuration;
+import org.springframework.context.annotation.Primary;
+import org.springframework.jdbc.core.JdbcTemplate;
+import org.springframework.jdbc.datasource.embedded.EmbeddedDatabaseBuilder;
+import org.springframework.test.annotation.DirtiesContext;
+import org.springframework.test.context.ContextConfiguration;
+import org.springframework.test.context.junit4.SpringJUnit4ClassRunner;
+import org.springframework.test.jdbc.JdbcTestUtils;
+import org.springframework.test.transaction.TransactionTestUtils;
+
+import static org.junit.Assert.*;
+
+/**
+ * Integration tests that ensure that <em>primary</em> data sources are
+ * supported.
+ *
+ * @author Sam Brannen
+ * @since 4.3
+ * @see org.springframework.test.context.transaction.PrimaryTransactionManagerTests
+ */
+@RunWith(SpringJUnit4ClassRunner.class)
+@ContextConfiguration
+@DirtiesContext
+public class PrimaryDataSourceTests {
+
+	@Configuration
+	static class Config {
+
+		@Primary
+		@Bean
+		public DataSource primaryDataSource() {
+			// @formatter:off
+			return new EmbeddedDatabaseBuilder()
+					.generateUniqueName(true)
+					.addScript("classpath:/org/springframework/test/context/jdbc/schema.sql")
+					.build();
+			// @formatter:on
+		}
+
+		@Bean
+		public DataSource additionalDataSource() {
+			return new EmbeddedDatabaseBuilder().generateUniqueName(true).build();
+		}
+
+	}
+
+
+	private JdbcTemplate jdbcTemplate;
+
+
+	@Autowired
+	public void setDataSource(DataSource dataSource) {
+		this.jdbcTemplate = new JdbcTemplate(dataSource);
+	}
+
+	@Test
+	@Sql("data.sql")
+	public void dataSourceTest() {
+		TransactionTestUtils.assertInTransaction(false);
+		assertEquals("Number of rows in the 'user' table.", 1,
+			JdbcTestUtils.countRowsInTable(this.jdbcTemplate, "user"));
+	}
+
+}

spring-test/src/test/java/org/springframework/test/context/transaction/PrimaryTransactionManagerTests.java

@@ -0,0 +1,122 @@
+/*
+ * Copyright 2002-2016 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.
+ * You may obtain a copy of the License at
+ *
+ *      http://www.apache.org/licenses/LICENSE-2.0
+ *
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
+ */
+
+package org.springframework.test.context.transaction;
+
+import javax.sql.DataSource;
+
+import org.junit.Test;
+import org.junit.runner.RunWith;
+
+import org.springframework.beans.factory.annotation.Autowired;
+import org.springframework.context.annotation.Bean;
+import org.springframework.context.annotation.Configuration;
+import org.springframework.context.annotation.Primary;
+import org.springframework.core.io.ClassPathResource;
+import org.springframework.jdbc.core.JdbcTemplate;
+import org.springframework.jdbc.datasource.DataSourceTransactionManager;
+import org.springframework.jdbc.datasource.embedded.EmbeddedDatabaseBuilder;
+import org.springframework.jdbc.datasource.init.ResourceDatabasePopulator;
+import org.springframework.test.annotation.DirtiesContext;
+import org.springframework.test.context.ContextConfiguration;
+import org.springframework.test.context.junit4.SpringJUnit4ClassRunner;
+import org.springframework.test.jdbc.JdbcTestUtils;
+import org.springframework.test.transaction.TransactionTestUtils;
+import org.springframework.transaction.PlatformTransactionManager;
+import org.springframework.transaction.annotation.Transactional;
+
+import static org.junit.Assert.*;
+
+/**
+ * Integration tests that ensure that <em>primary</em> transaction managers
+ * are supported.
+ *
+ * @author Sam Brannen
+ * @since 4.3
+ * @see org.springframework.test.context.jdbc.PrimaryDataSourceTests
+ */
+@RunWith(SpringJUnit4ClassRunner.class)
+@ContextConfiguration
+@DirtiesContext
+public class PrimaryTransactionManagerTests {
+
+	@Configuration
+	static class Config {
+
+		@Primary
+		@Bean
+		public PlatformTransactionManager primaryTransactionManager() {
+			return new DataSourceTransactionManager(dataSource1());
+		}
+
+		@Bean
+		public PlatformTransactionManager additionalTransactionManager() {
+			return new DataSourceTransactionManager(dataSource2());
+		}
+
+		@Bean
+		public DataSource dataSource1() {
+			// @formatter:off
+			return new EmbeddedDatabaseBuilder()
+					.generateUniqueName(true)
+					.addScript("classpath:/org/springframework/test/context/jdbc/schema.sql")
+					.build();
+			// @formatter:on
+		}
+
+		@Bean
+		public DataSource dataSource2() {
+			return new EmbeddedDatabaseBuilder().generateUniqueName(true).build();
+		}
+
+	}
+
+
+	private JdbcTemplate jdbcTemplate;
+
+
+	@Autowired
+	public void setDataSource(DataSource dataSource1) {
+		this.jdbcTemplate = new JdbcTemplate(dataSource1);
+	}
+
+	@BeforeTransaction
+	public void beforeTransaction() {
+		assertNumUsers(0);
+	}
+
+	@Test
+	@Transactional
+	public void transactionalTest() {
+		TransactionTestUtils.assertInTransaction(true);
+
+		ClassPathResource resource = new ClassPathResource("/org/springframework/test/context/jdbc/data.sql");
+		new ResourceDatabasePopulator(resource).execute(jdbcTemplate.getDataSource());
+
+		assertNumUsers(1);
+	}
+
+	@AfterTransaction
+	public void afterTransaction() {
+		assertNumUsers(0);
+	}
+
+	private void assertNumUsers(int expected) {
+		assertEquals("Number of rows in the 'user' table.", expected,
+			JdbcTestUtils.countRowsInTable(this.jdbcTemplate, "user"));
+	}
+
+}