Spring对Ibatis的封装

spring 对ibatis的封装通过SqlMapClientTemplate实现。

通常如果我们直接使用ibatis的sqlMapClient进行insert操作或者queryForObject都会抛出sqlSQLException:

	 try {
			cli.insert("MS-INSERT-UNREADCOUNT", unreadCount);
		} catch (SQLException e) {
			logger.error("create UnReadCount: ", e);
		}

处理这种错误很没意思,通过spring的sqlMapClientTemplate只需一行代码:
sqlMapClientTemplate.insert("MS-INSERT-UNREADCOUNT", unreadCount);

看看spring如何帮我们封装的:

	public <T> T execute(SqlMapClientCallback<T> action) throws DataAccessException {
		Assert.notNull(action, "Callback object must not be null");
		Assert.notNull(this.sqlMapClient, "No SqlMapClient specified");

		// We always need to use a SqlMapSession, as we need to pass a Spring-managed
		// Connection (potentially transactional) in. This shouldn't be necessary if
		// we run against a TransactionAwareDataSourceProxy underneath, but unfortunately
		// we still need it to make iBATIS batch execution work properly: If iBATIS
		// doesn't recognize an existing transaction, it automatically executes the
		// batch for every single statement...

		SqlMapSession session = this.sqlMapClient.openSession();
		if (logger.isDebugEnabled()) {
			logger.debug("Opened SqlMapSession [" + session + "] for iBATIS operation");
		}
		Connection ibatisCon = null;

		try {
			Connection springCon = null;
			DataSource dataSource = getDataSource();
			boolean transactionAware = (dataSource instanceof TransactionAwareDataSourceProxy);

			// Obtain JDBC Connection to operate on...
			try {
				ibatisCon = session.getCurrentConnection();
				if (ibatisCon == null) {
					springCon = (transactionAware ?
							dataSource.getConnection() : DataSourceUtils.doGetConnection(dataSource));
					session.setUserConnection(springCon);
					if (logger.isDebugEnabled()) {
						logger.debug("Obtained JDBC Connection [" + springCon + "] for iBATIS operation");
					}
				}
				else {
					if (logger.isDebugEnabled()) {
						logger.debug("Reusing JDBC Connection [" + ibatisCon + "] for iBATIS operation");
					}
				}
			}
			catch (SQLException ex) {
				throw new CannotGetJdbcConnectionException("Could not get JDBC Connection", ex);
			}

			// Execute given callback...
			try {
				return action.doInSqlMapClient(session);
			}
			catch (SQLException ex) {
				throw getExceptionTranslator().translate("SqlMapClient operation", null, ex);
			}
			finally {
				try {
					if (springCon != null) {
						if (transactionAware) {
							springCon.close();
						}
						else {
							DataSourceUtils.doReleaseConnection(springCon, dataSource);
						}
					}
				}
				catch (Throwable ex) {
					logger.debug("Could not close JDBC Connection", ex);
				}
			}

			// Processing finished - potentially session still to be closed.
		}
		finally {
			// Only close SqlMapSession if we know we've actually opened it
			// at the present level.
			if (ibatisCon == null) {
				session.close();
			}
		}
	}

最后所有的insert,update,delete,query都通过execute被执行。