Nullability fine-tuning around declaration inconsistencies

Issue: SPR-15720
Issue: SPR-15792

spring-jdbc/src/main/java/org/springframework/jdbc/InvalidResultSetAccessException.java

@@ -1,5 +1,5 @@
 /*
- * Copyright 2002-2012 the original author or authors.
+ * Copyright 2002-2017 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.
@@ -19,6 +19,7 @@ package org.springframework.jdbc;
 import java.sql.SQLException;
 
 import org.springframework.dao.InvalidDataAccessResourceUsageException;
+import org.springframework.lang.Nullable;
 
 /**
  * Exception thrown when a ResultSet has been accessed in an invalid fashion.
@@ -35,6 +36,7 @@ import org.springframework.dao.InvalidDataAccessResourceUsageException;
 @SuppressWarnings("serial")
 public class InvalidResultSetAccessException extends InvalidDataAccessResourceUsageException {
 
+	@Nullable
 	private String sql;
 
 
@@ -69,6 +71,7 @@ public class InvalidResultSetAccessException extends InvalidDataAccessResourceUs
 	 * Return the SQL that caused the problem.
 	 * @return the offending SQL, if known
 	 */
+	@Nullable
 	public String getSql() {
 		return this.sql;
 	}

spring-jdbc/src/main/java/org/springframework/jdbc/core/JdbcTemplate.java

@@ -515,6 +515,7 @@ public class JdbcTemplate extends JdbcAccessor implements JdbcOperations {
 
 		class BatchUpdateStatementCallback implements StatementCallback<int[]>, SqlProvider {
 
+			@Nullable
 			private String currSql;
 
 			@Override

spring-jdbc/src/main/java/org/springframework/jdbc/core/RowCountCallbackHandler.java

@@ -1,5 +1,5 @@
 /*
- * Copyright 2002-2012 the original author or authors.
+ * Copyright 2002-2017 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.
@@ -21,6 +21,7 @@ import java.sql.ResultSetMetaData;
 import java.sql.SQLException;
 
 import org.springframework.jdbc.support.JdbcUtils;
+import org.springframework.lang.Nullable;
 
 /**
  * Implementation of RowCallbackHandler. Convenient superclass for callback handlers.
@@ -54,11 +55,13 @@ public class RowCountCallbackHandler implements RowCallbackHandler {
 	 * Indexed from 0. Type (as in java.sql.Types) for the columns
 	 * as returned by ResultSetMetaData object.
 	 */
+	@Nullable
 	private int[] columnTypes;
 
 	/**
 	 * Indexed from 0. Column name as returned by ResultSetMetaData object.
 	 */
+	@Nullable
 	private String[] columnNames;
 
 
@@ -102,8 +105,9 @@ public class RowCountCallbackHandler implements RowCallbackHandler {
 	 * @return the types of the columns as java.sql.Types constants.
 	 * <b>Indexed from 0 to n-1.</b>
 	 */
+	@Nullable
 	public final int[] getColumnTypes() {
-		return columnTypes;
+		return this.columnTypes;
 	}
 
 	/**
@@ -112,8 +116,9 @@ public class RowCountCallbackHandler implements RowCallbackHandler {
 	 * @return the names of the columns.
 	 * <b>Indexed from 0 to n-1.</b>
 	 */
+	@Nullable
 	public final String[] getColumnNames() {
-		return columnNames;
+		return this.columnNames;
 	}
 
 	/**
@@ -122,7 +127,7 @@ public class RowCountCallbackHandler implements RowCallbackHandler {
 	 * @return the number of rows in this ResultSet
 	 */
 	public final int getRowCount() {
-		return rowCount;
+		return this.rowCount;
 	}
 
 	/**
@@ -132,7 +137,7 @@ public class RowCountCallbackHandler implements RowCallbackHandler {
 	 * @return the number of columns in this result set
 	 */
 	public final int getColumnCount() {
-		return columnCount;
+		return this.columnCount;
 	}
 
 }

spring-jdbc/src/main/java/org/springframework/jdbc/core/metadata/GenericCallMetaDataProvider.java

@@ -107,7 +107,7 @@ public class GenericCallMetaDataProvider implements CallMetaDataProvider {
 
 	@Override
 	public void initializeWithProcedureColumnMetaData(DatabaseMetaData databaseMetaData, @Nullable String catalogName,
-			@Nullable String schemaName, String procedureName) throws SQLException {
+			@Nullable String schemaName, @Nullable String procedureName) throws SQLException {
 
 		this.procedureColumnMetaDataUsed = true;
 		processProcedureColumns(databaseMetaData, catalogName, schemaName,  procedureName);

spring-jdbc/src/main/java/org/springframework/jdbc/core/simple/AbstractJdbcCall.java

@@ -71,12 +71,14 @@ public abstract class AbstractJdbcCall {
 	private volatile boolean compiled = false;
 
 	/** The generated string used for call statement */
+	@Nullable
 	private String callString;
 
 	/**
 	 * A delegate enabling us to create CallableStatementCreators
 	 * efficiently, based on this class's declared parameters.
 	 */
+	@Nullable
 	private CallableStatementCreatorFactory callableStatementFactory;
 
 
@@ -222,6 +224,7 @@ public abstract class AbstractJdbcCall {
 	/**
 	 * Get the call string that should be used based on parameters and meta data.
 	 */
+	@Nullable
 	public String getCallString() {
 		return this.callString;
 	}
@@ -230,6 +233,7 @@ public abstract class AbstractJdbcCall {
 	 * Get the {@link CallableStatementCreatorFactory} being used
 	 */
 	protected CallableStatementCreatorFactory getCallableStatementFactory() {
+		Assert.state(this.callableStatementFactory != null, "No CallableStatementCreatorFactory available");
 		return this.callableStatementFactory;
 	}
 
@@ -322,7 +326,7 @@ public abstract class AbstractJdbcCall {
 		}
 
 		this.callableStatementFactory =
-				new CallableStatementCreatorFactory(getCallString(), this.callMetaDataContext.getCallParameters());
+				new CallableStatementCreatorFactory(this.callString, this.callMetaDataContext.getCallParameters());
 
 		onCompileInternal();
 	}

spring-jdbc/src/main/java/org/springframework/jdbc/core/simple/AbstractJdbcInsert.java

@@ -81,9 +81,11 @@ public abstract class AbstractJdbcInsert {
 	private volatile boolean compiled = false;
 
 	/** The generated string used for insert statement */
+	@Nullable
 	private String insertString;
 
 	/** The SQL type information for the insert columns */
+	@Nullable
 	private int[] insertTypes;
 
 
@@ -222,6 +224,7 @@ public abstract class AbstractJdbcInsert {
 	/**
 	 * Get the insert string to be used.
 	 */
+	@Nullable
 	public String getInsertString() {
 		return this.insertString;
 	}
@@ -229,6 +232,7 @@ public abstract class AbstractJdbcInsert {
 	/**
 	 * Get the array of {@link java.sql.Types} to be used for insert.
 	 */
+	@Nullable
 	public int[] getInsertTypes() {
 		return this.insertTypes;
 	}
@@ -276,7 +280,7 @@ public abstract class AbstractJdbcInsert {
 		this.insertString = this.tableMetaDataContext.createInsertString(getGeneratedKeyNames());
 		this.insertTypes = this.tableMetaDataContext.createInsertTypes();
 		if (logger.isDebugEnabled()) {
-			logger.debug("Compiled insert object: insert string is [" + getInsertString() + "]");
+			logger.debug("Compiled insert object: insert string is [" + this.insertString + "]");
 		}
 		onCompileInternal();
 	}

spring-jdbc/src/main/java/org/springframework/jdbc/core/support/JdbcBeanDefinitionReader.java

@@ -22,6 +22,7 @@ import javax.sql.DataSource;
 import org.springframework.beans.factory.support.BeanDefinitionRegistry;
 import org.springframework.beans.factory.support.PropertiesBeanDefinitionReader;
 import org.springframework.jdbc.core.JdbcTemplate;
+import org.springframework.lang.Nullable;
 import org.springframework.util.Assert;
 
 /**
@@ -45,6 +46,7 @@ public class JdbcBeanDefinitionReader {
 
 	private final PropertiesBeanDefinitionReader propReader;
 
+	@Nullable
 	private JdbcTemplate jdbcTemplate;
 
 

spring-jdbc/src/main/java/org/springframework/jdbc/datasource/IsolationLevelDataSourceAdapter.java

@@ -126,7 +126,7 @@ public class IsolationLevelDataSourceAdapter extends UserCredentialsDataSourceAd
 	 * @see #getCurrentReadOnlyFlag()
 	 */
 	@Override
-	protected Connection doGetConnection(String username, String password) throws SQLException {
+	protected Connection doGetConnection(@Nullable String username, @Nullable String password) throws SQLException {
 		Connection con = super.doGetConnection(username, password);
 		Boolean readOnlyToUse = getCurrentReadOnlyFlag();
 		if (readOnlyToUse != null) {

spring-jdbc/src/main/java/org/springframework/jdbc/datasource/SimpleDriverDataSource.java

@@ -1,5 +1,5 @@
 /*
- * Copyright 2002-2016 the original author or authors.
+ * Copyright 2002-2017 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.
@@ -22,6 +22,7 @@ import java.sql.SQLException;
 import java.util.Properties;
 
 import org.springframework.beans.BeanUtils;
+import org.springframework.lang.Nullable;
 import org.springframework.util.Assert;
 
 /**
@@ -52,6 +53,7 @@ import org.springframework.util.Assert;
  */
 public class SimpleDriverDataSource extends AbstractDriverBasedDataSource {
 
+	@Nullable
 	private Driver driver;
 
 
@@ -117,13 +119,14 @@ public class SimpleDriverDataSource extends AbstractDriverBasedDataSource {
 	 * Driver instance.
 	 * @see #setDriverClass
 	 */
-	public void setDriver(Driver driver) {
+	public void setDriver(@Nullable Driver driver) {
 		this.driver = driver;
 	}
 
 	/**
 	 * Return the JDBC Driver instance to use.
 	 */
+	@Nullable
 	public Driver getDriver() {
 		return this.driver;
 	}

spring-jdbc/src/main/java/org/springframework/jdbc/datasource/WebSphereDataSourceAdapter.java

@@ -132,7 +132,7 @@ public class WebSphereDataSourceAdapter extends IsolationLevelDataSourceAdapter
 	 * @see com.ibm.websphere.rsadapter.WSDataSource#getConnection(com.ibm.websphere.rsadapter.JDBCConnectionSpec)
 	 */
 	@Override
-	protected Connection doGetConnection(String username, String password) throws SQLException {
+	protected Connection doGetConnection(@Nullable String username, @Nullable String password) throws SQLException {
 		// Create JDBCConnectionSpec using current isolation level value and read-only flag.
 		Object connSpec = createConnectionSpec(
 				getCurrentIsolationLevel(), getCurrentReadOnlyFlag(), username, password);

spring-jdbc/src/main/java/org/springframework/jdbc/datasource/init/DataSourceInitializer.java

@@ -38,8 +38,10 @@ public class DataSourceInitializer implements InitializingBean, DisposableBean {
 	@Nullable
 	private DataSource dataSource;
 
+	@Nullable
 	private DatabasePopulator databasePopulator;
 
+	@Nullable
 	private DatabasePopulator databaseCleaner;
 
 	private boolean enabled = true;

spring-jdbc/src/main/java/org/springframework/jdbc/support/xml/Jdbc4SqlXmlHandler.java

@@ -171,6 +171,7 @@ public class Jdbc4SqlXmlHandler implements SqlXmlHandler {
 	 */
 	private static abstract class AbstractJdbc4SqlXmlValue implements SqlXmlValue {
 
+		@Nullable
 		private SQLXML xmlObject;
 
 		@Override
@@ -187,11 +188,13 @@ public class Jdbc4SqlXmlHandler implements SqlXmlHandler {
 
 		@Override
 		public void cleanup() {
-			try {
-				this.xmlObject.free();
-			}
-			catch (SQLException ex) {
-				throw new DataAccessResourceFailureException("Could not free SQLXML object", ex);
+			if (this.xmlObject != null) {
+				try {
+					this.xmlObject.free();
+				}
+				catch (SQLException ex) {
+					throw new DataAccessResourceFailureException("Could not free SQLXML object", ex);
+				}
 			}
 		}