DATAJDBC-257 - Polishing.

Move container initialization from static initializer into createDataSource() to not trigger container start when loading the class.
Add TestExecutionListener to ignore tests if the license for a container was not accepted. Add Awaitility to delay test execution until the database is ready so we avoid strange failures due to a delayed container startup.

Fix generics, since tags, author tags. Reformat code.

Original pull request: #213.

pom.xml

@@ -25,6 +25,7 @@
 
 		<degraph-check.version>0.1.4</degraph-check.version>
 
+		<awaitility.version>4.0.2</awaitility.version>
 		<db2.version>11.5.0.0</db2.version>
 		<h2.version>1.4.200</h2.version>
 		<hsqldb.version>2.2.8</hsqldb.version>

spring-data-jdbc/pom.xml

@@ -151,6 +151,13 @@
 			<scope>test</scope>
 		</dependency>
 
+		<dependency>
+			<groupId>org.awaitility</groupId>
+			<artifactId>awaitility</artifactId>
+			<version>${awaitility.version}</version>
+			<scope>test</scope>
+		</dependency>
+
 		<dependency>
 			<groupId>org.assertj</groupId>
 			<artifactId>assertj-core</artifactId>
@@ -190,6 +197,7 @@
 			<groupId>com.ibm.db2</groupId>
 			<artifactId>jcc</artifactId>
 			<version>11.1.4.4</version>
+			<scope>test</scope>
 		</dependency>
 
 		<dependency>

spring-data-jdbc/src/test/java/org/springframework/data/jdbc/testing/Db2DataSourceConfiguration.java

@@ -15,29 +15,35 @@
  */
 package org.springframework.data.jdbc.testing;
 
+import java.sql.Connection;
+import java.sql.SQLException;
+
 import javax.sql.DataSource;
 
+import org.apache.commons.logging.Log;
+import org.apache.commons.logging.LogFactory;
+import org.awaitility.Awaitility;
+
 import org.springframework.context.annotation.Configuration;
 import org.springframework.context.annotation.Profile;
 import org.springframework.jdbc.datasource.DriverManagerDataSource;
 import org.springframework.jdbc.datasource.init.ResourceDatabasePopulator;
+
 import org.testcontainers.containers.Db2Container;
 
 /**
  * {@link DataSource} setup for DB2.
  *
  * @author Jens Schauder
- * @author Oliver Gierke
+ * @author Mark Paluch
  */
 @Configuration
 @Profile("db2")
 class Db2DataSourceConfiguration extends DataSourceConfiguration {
 
-	private static final Db2Container DB_2_CONTAINER = new Db2Container();
+	private static final Log LOG = LogFactory.getLog(Db2DataSourceConfiguration.class);
 
-	static {
-		DB_2_CONTAINER.start();
-	}
+	private static Db2Container DB_2_CONTAINER;
 
 	/*
 	 * (non-Javadoc)
@@ -46,12 +52,38 @@ class Db2DataSourceConfiguration extends DataSourceConfiguration {
 	@Override
 	protected DataSource createDataSource() {
 
+		if (DB_2_CONTAINER == null) {
+
+			LOG.info("DB2 starting...");
+			Db2Container container = new Db2Container();
+			container.start();
+			LOG.info("DB2 started");
+
+			DB_2_CONTAINER = container;
+		}
+
 		DriverManagerDataSource dataSource = new DriverManagerDataSource(DB_2_CONTAINER.getJdbcUrl(),
 				DB_2_CONTAINER.getUsername(), DB_2_CONTAINER.getPassword());
 
+		// DB2 container says its ready but it's like with a cat that denies service and still wants food although it had
+		// its food. Therefore, we make sure that we can properly establish a connection instead of trusting the cat
+		// ...err... DB2.
+		Awaitility.await().ignoreException(SQLException.class).until(() -> {
+
+			try (Connection connection = dataSource.getConnection()) {
+				return true;
+			}
+		});
+
+		LOG.info("DB2 connectivity verified");
+
 		return dataSource;
 	}
 
+	/*
+	 * (non-Javadoc)
+	 * @see org.springframework.data.jdbc.testing.customizePopulator#createDataSource(org.springframework.jdbc.datasource.init.ResourceDatabasePopulator)
+	 */
 	@Override
 	protected void customizePopulator(ResourceDatabasePopulator populator) {
 		populator.setIgnoreFailedDrops(true);

spring-data-jdbc/src/test/java/org/springframework/data/jdbc/testing/LicenseListener.java

@@ -0,0 +1,62 @@
+/*
+ * Copyright 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.
+ * You may obtain a copy of the License at
+ *
+ *      https://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.data.jdbc.testing;
+
+import org.junit.AssumptionViolatedException;
+
+import org.springframework.core.annotation.Order;
+import org.springframework.core.env.Profiles;
+import org.springframework.core.env.StandardEnvironment;
+import org.springframework.test.context.TestContext;
+import org.springframework.test.context.TestExecutionListener;
+
+import org.testcontainers.containers.Db2Container;
+import org.testcontainers.containers.MSSQLServerContainer;
+import org.testcontainers.utility.LicenseAcceptance;
+
+/**
+ * {@link TestExecutionListener} to selectively skip tests if the license for a particular database container was not
+ * accepted.
+ * 
+ * @author Mark Paluch
+ */
+@Order(Integer.MIN_VALUE)
+public class LicenseListener implements TestExecutionListener {
+
+	@Override
+	public void prepareTestInstance(TestContext testContext) {
+
+		StandardEnvironment environment = new StandardEnvironment();
+
+		if (environment.acceptsProfiles(Profiles.of("db2"))) {
+			assumeLicenseAccepted(Db2Container.DEFAULT_DB2_IMAGE_NAME + ":" + Db2Container.DEFAULT_TAG);
+		}
+
+		if (environment.acceptsProfiles(Profiles.of("mssql"))) {
+			assumeLicenseAccepted(MSSQLServerContainer.IMAGE + ":" + MSSQLServerContainer.DEFAULT_TAG);
+		}
+	}
+
+	private static void assumeLicenseAccepted(String imageName) {
+
+		try {
+			LicenseAcceptance.assertLicenseAccepted(imageName);
+		} catch (IllegalStateException e) {
+			throw new AssumptionViolatedException(e.getMessage());
+		}
+	}
+
+}

spring-data-jdbc/src/test/java/org/springframework/data/jdbc/testing/MariaDBDataSourceConfiguration.java

@@ -15,32 +15,32 @@
  */
 package org.springframework.data.jdbc.testing;
 
+import java.sql.Connection;
 import java.sql.SQLException;
 
 import javax.annotation.PostConstruct;
-import javax.script.ScriptException;
 import javax.sql.DataSource;
 
 import org.mariadb.jdbc.MariaDbDataSource;
+
 import org.springframework.context.annotation.Configuration;
 import org.springframework.context.annotation.Profile;
+import org.springframework.core.io.ByteArrayResource;
+import org.springframework.jdbc.datasource.init.ScriptUtils;
+
 import org.testcontainers.containers.MariaDBContainer;
-import org.testcontainers.jdbc.ext.ScriptUtils;
 
 /**
  * {@link DataSource} setup for MariaDB. Starts a Docker-container with a MariaDB database, and sets up database "test".
  * 
  * @author Christoph Preißner
+ * @author Mark Paluch
  */
 @Configuration
 @Profile("mariadb")
 class MariaDBDataSourceConfiguration extends DataSourceConfiguration {
 
-	private static final MariaDBContainer MARIADB_CONTAINER = new MariaDBContainer().withConfigurationOverride("");
-
-	static {
-		MARIADB_CONTAINER.start();
-	}
+	private static MariaDBContainer<?> MARIADB_CONTAINER;
 
 	/*
 	 * (non-Javadoc)
@@ -49,6 +49,14 @@ class MariaDBDataSourceConfiguration extends DataSourceConfiguration {
 	@Override
 	protected DataSource createDataSource() {
 
+		if (MARIADB_CONTAINER == null) {
+
+			MariaDBContainer<?> container = new MariaDBContainer<>().withConfigurationOverride("");
+			container.start();
+
+			MARIADB_CONTAINER = container;
+		}
+
 		try {
 
 			MariaDbDataSource dataSource = new MariaDbDataSource();
@@ -62,7 +70,12 @@ class MariaDBDataSourceConfiguration extends DataSourceConfiguration {
 	}
 
 	@PostConstruct
-	public void initDatabase() throws SQLException, ScriptException {
-		ScriptUtils.executeSqlScript(createDataSource().getConnection(), null, "DROP DATABASE test;CREATE DATABASE test;");
+	public void initDatabase() throws SQLException {
+
+		try (Connection connection = createDataSource().getConnection()) {
+			ScriptUtils.executeSqlScript(connection,
+					new ByteArrayResource("DROP DATABASE test;CREATE DATABASE test;".getBytes()));
 		}
+	}
+
 }

spring-data-jdbc/src/test/java/org/springframework/data/jdbc/testing/MsSqlDataSourceConfiguration.java

@@ -15,12 +15,14 @@
  */
 package org.springframework.data.jdbc.testing;
 
-import com.microsoft.sqlserver.jdbc.SQLServerDataSource;
+import javax.sql.DataSource;
+
 import org.springframework.context.annotation.Configuration;
 import org.springframework.context.annotation.Profile;
+
 import org.testcontainers.containers.MSSQLServerContainer;
 
-import javax.sql.DataSource;
+import com.microsoft.sqlserver.jdbc.SQLServerDataSource;
 
 
 /**
@@ -29,17 +31,14 @@ import javax.sql.DataSource;
  * Configuration for a MSSQL Datasource.
  *
  * @author Thomas Lang
+ * @author Mark Paluch
  * @see <a href="https://github.com/testcontainers/testcontainers-java/tree/master/modules/mssqlserver"></a>
  */
 @Configuration
 @Profile({"mssql"})
 public class MsSqlDataSourceConfiguration extends DataSourceConfiguration {
 
-    private static final MSSQLServerContainer mssqlserver = new MSSQLServerContainer();
-
-    static {
-        mssqlserver.start();
-    }
+	private static MSSQLServerContainer<?> MSSQL_CONTAINER;
 
     /*
      * (non-Javadoc)
@@ -48,10 +47,18 @@ public class MsSqlDataSourceConfiguration extends DataSourceConfiguration {
     @Override
     protected DataSource createDataSource() {
 
+		if (MSSQL_CONTAINER == null) {
+
+			MSSQLServerContainer<?> container = new MSSQLServerContainer<>();
+			container.start();
+
+			MSSQL_CONTAINER = container;
+		}
+
         SQLServerDataSource sqlServerDataSource = new SQLServerDataSource();
-        sqlServerDataSource.setURL(mssqlserver.getJdbcUrl());
-        sqlServerDataSource.setUser(mssqlserver.getUsername());
-        sqlServerDataSource.setPassword(mssqlserver.getPassword());
+		sqlServerDataSource.setURL(MSSQL_CONTAINER.getJdbcUrl());
+		sqlServerDataSource.setUser(MSSQL_CONTAINER.getUsername());
+		sqlServerDataSource.setPassword(MSSQL_CONTAINER.getPassword());
         return sqlServerDataSource;
     }
 }

spring-data-jdbc/src/test/java/org/springframework/data/jdbc/testing/MySqlDataSourceConfiguration.java

@@ -15,19 +15,18 @@
  */
 package org.springframework.data.jdbc.testing;
 
+import java.sql.Connection;
 import java.sql.SQLException;
 
 import javax.annotation.PostConstruct;
-import javax.script.ScriptException;
 import javax.sql.DataSource;
 
-import org.springframework.context.annotation.Bean;
 import org.springframework.context.annotation.Configuration;
 import org.springframework.context.annotation.Profile;
-import org.springframework.data.relational.core.dialect.Dialect;
-import org.springframework.data.relational.core.dialect.MySqlDialect;
+import org.springframework.core.io.ByteArrayResource;
+import org.springframework.jdbc.datasource.init.ScriptUtils;
+
 import org.testcontainers.containers.MySQLContainer;
-import org.testcontainers.jdbc.ext.ScriptUtils;
 
 import com.mysql.jdbc.jdbc2.optional.MysqlDataSource;
 
@@ -38,16 +37,13 @@ import com.mysql.jdbc.jdbc2.optional.MysqlDataSource;
  * @author Jens Schauder
  * @author Oliver Gierke
  * @author Sedat Gokcen
+ * @author Mark Paluch
  */
 @Configuration
 @Profile("mysql")
 class MySqlDataSourceConfiguration extends DataSourceConfiguration {
 
-	private static final MySQLContainer MYSQL_CONTAINER = new MySQLContainer().withConfigurationOverride("");
-
-	static {
-		MYSQL_CONTAINER.start();
-	}
+	private static MySQLContainer<?> MYSQL_CONTAINER;
 
 	/*
 	 * (non-Javadoc)
@@ -56,6 +52,14 @@ class MySqlDataSourceConfiguration extends DataSourceConfiguration {
 	@Override
 	protected DataSource createDataSource() {
 
+		if (MYSQL_CONTAINER == null) {
+
+			MySQLContainer<?> container = new MySQLContainer<>().withConfigurationOverride("");
+			container.start();
+
+			MYSQL_CONTAINER = container;
+		}
+
 		MysqlDataSource dataSource = new MysqlDataSource();
 		dataSource.setUrl(MYSQL_CONTAINER.getJdbcUrl());
 		dataSource.setUser(MYSQL_CONTAINER.getUsername());
@@ -66,7 +70,11 @@ class MySqlDataSourceConfiguration extends DataSourceConfiguration {
 	}
 
 	@PostConstruct
-	public void initDatabase() throws SQLException, ScriptException {
-		ScriptUtils.executeSqlScript(createDataSource().getConnection(), null, "DROP DATABASE test;CREATE DATABASE test;");
+	public void initDatabase() throws SQLException {
+
+		try (Connection connection = createDataSource().getConnection()) {
+			ScriptUtils.executeSqlScript(connection,
+					new ByteArrayResource("DROP DATABASE test;CREATE DATABASE test;".getBytes()));
+		}
 	}
 }

spring-data-jdbc/src/test/java/org/springframework/data/jdbc/testing/PostgresDataSourceConfiguration.java

@@ -18,12 +18,11 @@ package org.springframework.data.jdbc.testing;
 import javax.sql.DataSource;
 
 import org.postgresql.ds.PGSimpleDataSource;
-import org.springframework.context.annotation.Bean;
+
 import org.springframework.context.annotation.Configuration;
 import org.springframework.context.annotation.Profile;
-import org.springframework.data.relational.core.dialect.Dialect;
-import org.springframework.data.relational.core.dialect.PostgresDialect;
 import org.springframework.jdbc.datasource.init.ResourceDatabasePopulator;
+
 import org.testcontainers.containers.PostgreSQLContainer;
 
 /**
@@ -32,16 +31,13 @@ import org.testcontainers.containers.PostgreSQLContainer;
  * @author Jens Schauder
  * @author Oliver Gierke
  * @author Sedat Gokcen
+ * @author Mark Paluch
  */
 @Configuration
 @Profile("postgres")
 public class PostgresDataSourceConfiguration extends DataSourceConfiguration {
 
-	private static final PostgreSQLContainer POSTGRESQL_CONTAINER = new PostgreSQLContainer();
-
-	static {
-		POSTGRESQL_CONTAINER.start();
-	}
+	private static PostgreSQLContainer<?> POSTGRESQL_CONTAINER;
 
 	/*
 	 * (non-Javadoc)
@@ -50,6 +46,14 @@ public class PostgresDataSourceConfiguration extends DataSourceConfiguration {
 	@Override
 	protected DataSource createDataSource() {
 
+		if (POSTGRESQL_CONTAINER == null) {
+
+			PostgreSQLContainer<?> container = new PostgreSQLContainer<>();
+			container.start();
+
+			POSTGRESQL_CONTAINER = container;
+		}
+
 		PGSimpleDataSource dataSource = new PGSimpleDataSource();
 		dataSource.setUrl(POSTGRESQL_CONTAINER.getJdbcUrl());
 		dataSource.setUser(POSTGRESQL_CONTAINER.getUsername());

spring-data-jdbc/src/test/resources/META-INF/spring.factories

@@ -0,0 +1 @@
+org.springframework.test.context.TestExecutionListener=org.springframework.data.jdbc.testing.LicenseListener

spring-data-jdbc/src/test/resources/logback.xml

@@ -7,6 +7,7 @@
 		</encoder>
 	</appender>
 
+	<logger name="org.springframework.test.context.TestContextManager" level="off" />
 	<!--<logger name="org.springframework.data" level="info" />-->
 	<!--<logger name="org.springframework.jdbc.core" level="trace" />-->
 	<!--<logger name="org.springframework.data.jdbc.mybatis.DummyEntityMapper" level="trace" />-->

spring-data-relational/src/main/java/org/springframework/data/relational/core/dialect/Db2Dialect.java

@@ -21,7 +21,7 @@ import org.springframework.data.relational.core.sql.IdentifierProcessing;
  * An SQL dialect for DB2.
  *
  * @author Jens Schauder
- * @since 2.1
+ * @since 2.0
  */
 public class Db2Dialect extends AbstractDialect {
 
@@ -80,6 +80,10 @@ public class Db2Dialect extends AbstractDialect {
 		return LIMIT_CLAUSE;
 	}
 
+	/*
+	 * (non-Javadoc)
+	 * @see org.springframework.data.relational.core.dialect.Dialect#getIdentifierProcessing()
+	 */
 	@Override
 	public IdentifierProcessing getIdentifierProcessing() {
 		return IdentifierProcessing.ANSI;