rdbmsoperation.java

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/*
 * Copyright 2002-2006 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.jdbc.object;

import java.sql.ResultSet;
import java.sql.Types;
import java.util.Iterator;
import java.util.LinkedList;
import java.util.List;
import java.util.Map;

import javax.sql.DataSource;

import org.apache.commons.logging.Log;
import org.apache.commons.logging.LogFactory;

import org.springframework.beans.factory.InitializingBean;
import org.springframework.dao.InvalidDataAccessApiUsageException;
import org.springframework.jdbc.core.JdbcTemplate;
import org.springframework.jdbc.core.ResultSetSupportingSqlParameter;
import org.springframework.jdbc.core.SqlParameter;

/**
 * An "RDBMS operation" is a multithreaded, reusable object representing a
 * query, update or stored procedure. An RDBMS operation is <b>not</b> a command,
 * as a command isn't reusable. However, execute methods may take commands as
 * arguments. Subclasses should be Java beans, allowing easy configuration.
 *
 * <p>Root of the JDBC object hierarchy, as described in Chapter 9 of
 * <a href="http://www.amazon.com/exec/obidos/tg/detail/-/0764543857/">
 * Expert One-On-One J2EE Design and Development</a> by Rod Johnson (Wrox, 2002).
 *
 * <p>This class and subclasses throw runtime exceptions, defined in the
 * <codeorg.springframework.dao package</code> (and as thrown by the
 * <code>org.springframework.jdbc.core</code> package, which the classes
 * in this package use under the hood to perform raw JDBC operations).
 *
 * <p>Subclasses should set SQL and add parameters before invoking the
 * <code>compile()</code> method. The order in which parameters are added is
 * significant. The appropriate <code>execute</code> or <code>update</code>
 * method can then be invoked.
 *
 * @author Rod Johnson
 * @author Juergen Hoeller
 * @see #compile
 * @see org.springframework.dao
 * @see org.springframework.jdbc.core
 */
public abstract class RdbmsOperation implements InitializingBean {

	protected final Log logger = LogFactory.getLog(getClass());

	/** Lower-level class used to execute SQL */
	private JdbcTemplate jdbcTemplate = new JdbcTemplate();

	private int resultSetType = ResultSet.TYPE_FORWARD_ONLY;

	private boolean updatableResults = false;

	private boolean returnGeneratedKeys = false;
	
	private String[] generatedKeysColumnNames = null;

	/** SQL statement */
	private String sql;

	/** List of SqlParameter objects */
	private List declaredParameters = new LinkedList();

	/**
	 * Has this operation been compiled? Compilation means at
	 * least checking that a DataSource and sql have been provided,
	 * but subclasses may also implement their own custom validation.
	 */
	private boolean compiled;
	
	
	/**
	 * An alternative to the more commonly used setDataSource() when you want to
	 * use the same JdbcTemplate in multiple RdbmsOperations. This is appropriate if the
	 * JdbcTemplate has special configuration such as a SQLExceptionTranslator that should
	 * apply to multiple RdbmsOperation objects.
	 */
	public void setJdbcTemplate(JdbcTemplate jdbcTemplate) {
		if (jdbcTemplate == null) {
			throw new IllegalArgumentException("jdbcTemplate must not be null");
		}
		this.jdbcTemplate = jdbcTemplate;
	}

	/**
	 * Return the JdbcTemplate object used by this object.
	 */
	public JdbcTemplate getJdbcTemplate() {
		return jdbcTemplate;
	}

	/**
	 * Set the JDBC DataSource to obtain connections from.
	 * @see org.springframework.jdbc.core.JdbcTemplate#setDataSource
	 */
	public void setDataSource(DataSource dataSource) {
		this.jdbcTemplate.setDataSource(dataSource);
	}

	/**
	 * Set the fetch size for this RDBMS operation. This is important for processing
	 * large result sets: Setting this higher than the default value will increase
	 * processing speed at the cost of memory consumption; setting this lower can
	 * avoid transferring row data that will never be read by the application.
	 * <p>Default is 0, indicating to use the driver's default.
	 * @see org.springframework.jdbc.core.JdbcTemplate#setFetchSize
	 */
	public void setFetchSize(int fetchSize) {
		this.jdbcTemplate.setFetchSize(fetchSize);
	}

	/**
	 * Set the maximum number of rows for this RDBMS operation. This is important
	 * for processing subsets of large result sets, avoiding to read and hold
	 * the entire result set in the database or in the JDBC driver.
	 * <p>Default is 0, indicating to use the driver's default.
	 * @see org.springframework.jdbc.core.JdbcTemplate#setMaxRows
	 */
	public void setMaxRows(int maxRows) {
		this.jdbcTemplate.setMaxRows(maxRows);
	}

	/**
	 * Set whether to use statements that return a specific type of ResultSet.
	 * @param resultSetType the ResultSet type
	 * @see java.sql.ResultSet#TYPE_FORWARD_ONLY
	 * @see java.sql.ResultSet#TYPE_SCROLL_INSENSITIVE
	 * @see java.sql.ResultSet#TYPE_SCROLL_SENSITIVE
	 * @see java.sql.Connection#prepareStatement(String, int, int)
	 */
	public void setResultSetType(int resultSetType) {
		this.resultSetType = resultSetType;
	}

	/**
	 * Return whether statements will return a specific type of ResultSet.
	 */
	public int getResultSetType() {
		return resultSetType;
	}

	/**
	 * Set whether to use statements that are capable of returning
	 * updatable ResultSets.
	 * @see java.sql.Connection#prepareStatement(String, int, int)
	 */
	public void setUpdatableResults(boolean updatableResults) {
		if (isCompiled()) {
			throw new InvalidDataAccessApiUsageException(
					"The updateableResults flag must be set before the operation is compiled");
		}
		this.updatableResults = updatableResults;
	}

	/**
	 * Return whether statements will return updatable ResultSets.
	 */
	public boolean isUpdatableResults() {
		return updatableResults;
	}

	/**
	 * Set whether prepared statements should be capable of returning
	 * auto-generated keys.
	 * @see java.sql.Connection#prepareStatement(String, int)
	 */
	public void setReturnGeneratedKeys(boolean returnGeneratedKeys) {
		if (isCompiled()) {
			throw new InvalidDataAccessApiUsageException(
					"The returnGeneratedKeys flag must be set before the operation is compiled");
		}
		this.returnGeneratedKeys = returnGeneratedKeys;
	}

	/**
	 * Return whether statements should be capable of returning
	 * auto-generated keys.
	 */
	public boolean isReturnGeneratedKeys() {
		return returnGeneratedKeys;
	}

	/**
	 * Set the column names of the auto-generated keys.
	 * @see java.sql.Connection#prepareStatement(String, String[])
	 */
	public void setGeneratedKeysColumnNames(String[] names) {
		if (isCompiled()) {
			throw new InvalidDataAccessApiUsageException(
					"The column names for the generated keys must be set before the operation is compiled");
		}
		this.generatedKeysColumnNames = names;
	}

	/**
	 * Return the column names of the auto generated keys.
	 */
	public String[] getGeneratedKeysColumnNames() {
		return generatedKeysColumnNames;
	}

	/**
	 * Set the SQL executed by this operation.
	 */
	public void setSql(String sql) {
		this.sql = sql;
	}

	/**
	 * Subclasses can override this to supply dynamic SQL if they wish,
	 * but SQL is normally set by calling the setSql() method
	 * or in a subclass constructor.
	 */
	public String getSql() {