在iBatis中加入c3p0数据库连接池

我看论坛里有两个人写了在iBatis中加入c3p0，我也就不跟着掺合了，做这个的原因是没法用spring，又需要连接池，且对DBCP一直观感不加，没法，只好自己动手了

在iBatis中加入c3p0没啥难技术含量，写个文章备份下

首先打开iBatis的源码包，找到com.ibatis.sqlmap.engine.datasource包，在里面新建个类
C3p0DataSourceFactory，并实现DataSourceFactory接口，里面的代码是

	private DataSource dataSource;
	
	public DataSource getDataSource() {
		return dataSource;
	}

	public void initialize(Map map) {
		C3p0Configuration c3p0 = new C3p0Configuration(map);
	    dataSource = c3p0.getDataSource();
	}

然后到com.ibatis.common.jdbc包里，新建类C3p0Configuration，里面的代码是。。。太长了，先给个片段，具体的下载附件吧，原来在dbcp那部分里，还有单独加载配置文件的方法，我觉得如果连这个xml都读不了，那别的一样没法读

	private static final Probe PROBE = ProbeFactory.getProbe();
	private DataSource dataSource;

	/**
	 * Constructor to supply a map of properties
	 * 
	 * @param properties
	 *            - the map of configuration properties
	 */
	public C3p0Configuration(Map properties) {
		try {
			dataSource = legacyC3p0Configuration(properties);
		} catch (Exception e) {
			throw new RuntimeException(
					"Error initializing C3p0DataSourceFactory.  Cause: " + e, e);
		}
	}

	/**
	 * Getter for DataSource
	 * 
	 * @return The DataSource
	 */
	public DataSource getDataSource() {
		return dataSource;
	}

	private boolean notEmpty(String s) {
		return s != null && s.length() > 0;
	}

	private boolean notSelfString(String s, String compareStr) {
		return !s.equalsIgnoreCase(compareStr);
	}

	private DataSource legacyC3p0Configuration(Map map) {

		ComboPooledDataSource combo = null;

		try {
			if (map.containsKey("JDBC.Driver")) {

				combo = new ComboPooledDataSource();

				String driverClass = (String) map.get("JDBC.Driver");
				String jdbcUrl = (String) map.get("JDBC.ConnectionURL");
				String user = (String) map.get("JDBC.Username");
				String password = (String) map.get("JDBC.Password");

				Class.forName(driverClass);
				combo.setDriverClass(driverClass);
				combo.setJdbcUrl(jdbcUrl);
				combo.setUser(user);
				combo.setPassword(password);

				String acquireIncrement = (String) map
						.get("Pool.acquireIncrement");
				if (notEmpty(acquireIncrement)
						&& notSelfString(acquireIncrement, "acquireIncrement"))
					combo.setAcquireIncrement(Integer
							.parseInt(acquireIncrement));

......................

最后在com.ibatis.sqlmap.engine.config包里，找到SqlMapConfiguration，在里面找到，加上C3P0就好了

    // DATA SOURCE ALIASES
    typeHandlerFactory.putTypeAlias("SIMPLE", SimpleDataSourceFactory.class.getName());
    typeHandlerFactory.putTypeAlias("DBCP", DbcpDataSourceFactory.class.getName());
    typeHandlerFactory.putTypeAlias("C3P0", C3p0DataSourceFactory.class.getName());
    typeHandlerFactory.putTypeAlias("JNDI", JndiDataSourceFactory.class.getName());

具体的源码看附件吧，文件名是“iBatis添加c3p0.rar”里面有c3p0-config.properties和SqlMapConfig.xml

还有打包好的ibatis jar，在附件里，名字是ibatis-2.3.4.726-c3p0.jar

评论

3 楼 zuzong 2009-06-13  

补遗：

private boolean notSelfString(String s, String compareStr) { 
        return !s.equalsIgnoreCase(compareStr); 
    }

原来在ibatis的DBCP里，没这项判断，但我测试时发现，如果在SqlMapConfig.xml里，
类似这项
<property name="Pool.description" value="${description}"/>

当${description}是空值时，就会直接传入EL里面的字符串description

所以，如果EL式里面的字符串变了，这个判断就没治了。。。

2 楼 shunzheheliu 2009-06-13  

木用过ibatis还有c3p0，非常纯洁的顶【支持】一下

1 楼 孙宁振 2009-06-13  

木用过ibatis，纯洁的支持一下