先通过一个小例子，简单使用一下。

?

配置文件 applicationContext.xml

?

<beans  default-autowire ="autodetect"> 
     <bean id ="dataSource"  class ="org.apache.commons.dbcp.BasicDataSource">  
         <property name ="driverClassName">  
             <value>oracle.jdbc.driver.OracleDriver</value>  
         </property>  
         <property name ="url">  
             <value>jdbc:oracle:thin:@localhost:1521:orcl</value> 
          </property> 
         <property name="username"> 
             <value>username</value> 
         </property> 
         <property name="password"> 
             <value>password</value> 
         </property> 
         <property name="maxActive"> 
             <value>10</value> 
         </property> 
         <property name="maxIdle"> 
             <value>2</value> 
         </property> 
     </bean> 

     <bean id ="JdbcTemplate"
         class ="org.springframework.jdbc.core.JdbcTemplate"> 
         <property name ="dataSource"> 
             <ref bean ="dataSource"  /> 
         </property> 
     </bean> 
 </beans> 

?

程序

	public static void main(String[] args) {
		
		ClassPathResource res = new ClassPathResource("applicationContext.xml");
		XmlBeanFactory factory = new XmlBeanFactory(res);
		JdbcTemplate jdbcTemplate = (JdbcTemplate) factory
				.getBean("JdbcTemplate");
	 
		jdbcTemplate
				.update("delete from TB_USER where ID= 466 ");
	}

?

只需要一句代码,? 就完成了我们关心的 jdbc 操作。

?

F3，看下 jdbcTemplate.update 的实现，

?

	public int update(final String sql) throws DataAccessException {
		Assert.notNull(sql, "SQL must not be null");
		if (logger.isDebugEnabled()) {
			logger.debug("Executing SQL update [" + sql + "]");
		}

		class UpdateStatementCallback implements StatementCallback, SqlProvider {
			public Object doInStatement(Statement stmt) throws SQLException {
				int rows = stmt.executeUpdate(sql);
				if (logger.isDebugEnabled()) {
					logger.debug("SQL update affected " + rows + " rows");
				}
				return new Integer(rows);
			}
			public String getSql() {
				return sql;
			}
		}
		return ((Integer) execute(new UpdateStatementCallback())).intValue();
	}

?

	public Object execute(StatementCallback action) throws DataAccessException {
		Assert.notNull(action, "Callback object must not be null");

		Connection con = DataSourceUtils.getConnection(getDataSource());
		Statement stmt = null;
		try {
			Connection conToUse = con;
			if (this.nativeJdbcExtractor != null &&
					this.nativeJdbcExtractor.isNativeConnectionNecessaryForNativeStatements()) {
				conToUse = this.nativeJdbcExtractor.getNativeConnection(con);
			}
			stmt = conToUse.createStatement();
			applyStatementSettings(stmt);
			Statement stmtToUse = stmt;
			if (this.nativeJdbcExtractor != null) {
				stmtToUse = this.nativeJdbcExtractor.getNativeStatement(stmt);
			}
			Object result = action.doInStatement(stmtToUse);
			handleWarnings(stmt.getWarnings());
			return result;
		}
		catch (SQLException ex) {
			// Release Connection early, to avoid potential connection pool deadlock
			// in the case when the exception translator hasn't been initialized yet.
			JdbcUtils.closeStatement(stmt);
			stmt = null;
			DataSourceUtils.releaseConnection(con, getDataSource());
			con = null;
			throw getExceptionTranslator().translate("StatementCallback", getSql(action), ex);
		}
		finally {
			JdbcUtils.closeStatement(stmt);
			DataSourceUtils.releaseConnection(con, getDataSource());
		}
	}

这里就用到了 Template 设计模式，估计Spring 的这个模块叫 JdbcTempla