XApool连接池报空指针错误解决

at org.enhydra.jdbc.pool.GenericPool.getFromPool(GenericPool.java:200) 
at org.enhydra.jdbc.pool.GenericPool.checkOut(GenericPool.java:351) 
at org.enhydra.jdbc.pool.StandardPoolDataSource.getConnection(StandardPoolDataSource.java:194) 
at org.enhydra.jdbc.pool.StandardPoolDataSource.getConnection(StandardPoolDataSource.java:164) 
at my.jotm.test.Client.getConnection(Client.java:63) 
java.sql.SQLException: SQLException in StandardPoolDataSource:getConnection exception: java.sql.SQLException: SQLException in  
StandardPoolDataSource:getConnection no connection available java.lang.NullPointerException

 
发现这是XApool1.5的一个bug

解决方法：

--- xapool/org/enhydra/jdbc/pool/GenericPool.java-1.13 2005-06-14 21:57:10.756790600 -0500 +++ xapool/org/enhydra/jdbc/pool/GenericPool.java 2005-06-15 13:11:09.601072300 -0500 @@ -189,6 +189,12 @@ o = (GenerationObject) e.nextElement(); life = (Long) unlocked.get(o); + if (life == null) { + // Fix for #303462; note that this fixes the problem, but Enumeration's on Hashtable's + // are by definition somewhat unpredictable; a more robust fix may be in order + log.debug("GenericPool:getFromPool fix for #303462 encountered"); + continue; + } unlocked.remove(o); // In any case the object will be removed. // Prevents others accessing the object while we are

下载xapool源码包，然后在org.enhydra.jdbc.pool.GenericPool中，找到life = (Long) unlocked.get(o); 代码

之后在下面加入：

if (life == null)  continue;

之后重新编译打包即可。

注：xapool1.5是在jdk1.4的版本下编译的，所以记得在打包修改时，将IDE的J2SE版本改为1.4。

以下提供我已经编译好的jar包，使用中如果看到bad version的错误，请自行编译。