数据库连接池类有错误，请高手给我看看是怎么回事

Question

public class Conn{
private DataSource ds = null;
public Conn(){}
public Connection getConnection(){
Connection connection=null;
try{
Context ctx = new InitialContext();
ds = (DataSource)ctx.lookup("jdbc/zdxt");
connection=ds.getConnection();
}catch(Exception e){
e.getMessage();
}
return connection;
}
/**
* 查询
* @param sql String
* @return ResultSet
*/
public ResultSet executeQuery(String sql){
ResultSet rs=null;
Connection conn=null;
try{
conn=getConnection();
Statement stmt=conn.createStatement(ResultSet.TYPE_SCROLL_INSENSITIVE,ResultSet.CONCUR_READ_ONLY);
rs=stmt.executeQuery(sql);
}catch(SQLException e){
e.printStackTrace();
}finally{
try{
if(conn != null){
conn.close();
}
}catch(Exception e){
e.printStackTrace();
}
}
return rs;
}
/**
* 更新
* @param sql String
* @return int
*/
public int executeUpdate(String sql){
int i=0;
Connection conn=null;
try{
conn=getConnection();
Statement stmt=conn.createStatement(ResultSet.TYPE_SCROLL_INSENSITIVE,ResultSet.CONCUR_READ_ONLY);
i=stmt.executeUpdate(sql);
}catch(SQLException e){
e.printStackTrace();
}finally{
try{
if(conn != null){
conn.close();
}
}catch(Exception e){
e.printStackTrace();
}
}
return i;
}
}

Answer 1

直接用print会遮盖错误
还是按照我上面的写法写吧然后把错误码贴上来
就可以帮你解决了

Answer 2

Statement stmt=conn.createStatement(ResultSet.TYPE_SCROLL_INSENSITIVE,ResultSet.CONCUR_READ_ONLY);
      i=stmt.executeUpdate(sql);
是不是CONCUR_READ_ONLY，而你却使用了update语句所导致的。
具体的还要把错误帖出来才能分析。

Answer 3

改成 ds = (DataSource) ctx.lookup("java:comp/env/jdbc/zdxt");

Answer 4

应该是没有关闭Statement和resultset的问题。

Answer 5

错误:
java.lang.NullPointerException
        at com.zht.framework.Authority.authority(Authority.java:28)
        at _jasper._xsdwgl._show_pyc_jsp._jspService(_show_pyc_jsp.java:127)
        at org.apache.jasper.runtime.HttpJspBase.service(HttpJspBase.java:107)
        at javax.servlet.http.HttpServlet.service(HttpServlet.java:853)
        at com.iplanet.ias.web.jsp.JspServlet$JspServletWrapper.service(JspServl
et.java:552)
        at com.iplanet.ias.web.jsp.JspServlet.serviceJspFile(JspServlet.java:368
)
        at com.iplanet.ias.web.jsp.JspServlet.service(JspServlet.java:287)
        at javax.servlet.http.HttpServlet.service(HttpServlet.java:853)
        at org.apache.catalina.core.StandardWrapperValve.invokeServletService(St
andardWrapperValve.java:720)
        at org.apache.catalina.core.StandardWrapperValve.access$000(StandardWrap
perValve.java:118)
        at org.apache.catalina.core.StandardWrapperValve$1.run(StandardWrapperVa
lve.java:278)
        at java.security.AccessController.doPrivileged(Native Method)
        at org.apache.catalina.core.StandardWrapperValve.invoke(StandardWrapperV
alve.java:274)
        at org.apache.catalina.core.StandardPipeline.invoke(StandardPipeline.jav
a:505)
        at org.apache.catalina.core.StandardContextValve.invoke(StandardContextV
alve.java:212)
        at org.apache.catalina.core.StandardPipeline.invoke(StandardPipeline.jav
a:505)
        at org.apache.catalina.core.StandardHostValve.invoke(StandardHostValve.j
ava:203)
        at org.apache.catalina.core.StandardPipeline.invoke(StandardPipeline.jav
a:505)
        at com.iplanet.ias.web.connector.nsapi.NSAPIProcessor.process(NSAPIProce
ssor.java:158)
        at com.iplanet.ias.web.WebContainer.service(WebContainer.java:598)WARNING: CORE3283: stderr:      at org.apache.catalina.core.StandardWrapperValve
.invoke(StandardWrapperValve.java:274)
WARNING: CORE3283: stderr:      at org.apache.catalina.core.StandardPipeline.inv
oke(StandardPipeline.java:505)
WARNING: CORE3283: stderr:      at org.apache.catalina.core.StandardContextValve
.invoke(StandardContextValve.java:212)
WARNING: CORE3283: stderr:      at org.apache.catalina.core.StandardPipeline.inv
oke(StandardPipeline.java:505)
WARNING: CORE3283: stderr:      at org.apache.catalina.core.StandardHostValve.in
voke(StandardHostValve.java:203)
WARNING: CORE3283: stderr:      at org.apache.catalina.core.StandardPipeline.inv
oke(StandardPipeline.java:505)
WARNING: CORE3283: stderr:      at com.iplanet.ias.web.connector.nsapi.NSAPIProc
essor.process(NSAPIProcessor.java:158)
WARNING: CORE3283: stderr:      at com.iplanet.ias.web.WebContainer.service(WebC
ontainer.java:598)
WARNING: CORE3283: stderr: java.sql.SQLException: ORA-01000: 超出打开游标的最大
数
WARNING: CORE3283: stderr:      at oracle.jdbc.dbaccess.DBError.throwSqlExceptio
n(DBError.java)
WARNING: CORE3283: stderr:      at oracle.jdbc.ttc7.TTIoer.processError(TTIoer.j
ava)
WARNING: CORE3283: stderr:      at oracle.jdbc.ttc7.Oopen.receive(Oopen.java)
WARNING: CORE3283: stderr:      at oracle.jdbc.ttc7.TTC7Protocol.open(TTC7Protoc
ol.java)
WARNING: CORE3283: stderr:      at oracle.jdbc.driver.OracleStatement.<init>(Ora
cleStatement.java)
WARNING: CORE3283: stderr:      at oracle.jdbc.driver.OracleStatement.<init>(Ora
cleStatement.java)
WARNING: CORE3283: stderr:      at oracle.jdbc.driver.OracleConnection.privateCr
eateStatement(OracleConnection.java)
WARNING: CORE3283: stderr:      at oracle.jdbc.driver.OracleConnection.createSta
tement(OracleConnection.java)
WARNING: CORE3283: stderr:      at com.sun.enterprise.resource.JdbcXAConnection$
JdbcConnection.createStatement(JdbcXAConnection.java:568)
WARNING: CORE3283: stderr:      at com.zht.DBConn.Conn.executeQuery(Conn.java:33
)
WARNING: CORE3283: stderr:      at com.zht.framework.Authority.authority(Authori
ty.java:26)
WARNING: CORE3283: stderr:      at _jasper._xsdwgl._show_pyc_jsp._jspService(_sh
ow_pyc_jsp.java:127)
WARNING: CORE3283: stderr:      at org.apache.jasper.runtime.HttpJspBase.service
(HttpJspBase.java:107)
WARNING: CORE3283: stderr:      at javax.servlet.http.HttpServlet.service(HttpSe
rvlet.java:853)
WARNING: CORE3283: stderr:      at com.iplanet.ias.web.jsp.JspServlet$JspServlet
Wrapper.service(JspServlet.java:552)
WARNING: CORE3283: stderr:      at com.iplanet.ias.web.jsp.JspServlet.serviceJsp
File(JspServlet.java:368)
WARNING: CORE3283: stderr:      at com.iplanet.ias.web.jsp.JspServlet.service(Js
pServlet.java:287)
WARNING: CORE3283: stderr:      at javax.servlet.http.HttpServlet.service(HttpSe
rvlet.java:853)
WARNING: CORE3283: stderr:      at org.apache.catalina.core.StandardWrapperValve
.invokeServletService(StandardWrapperValve.java:720)
WARNING: CORE3283: stderr:      at org.apache.catalina.core.StandardWrapperValve
.access$000(StandardWrapperValve.java:118)
WARNING: CORE3283: stderr:      at org.apache.catalina.core.StandardWrapperValve
$1.run(StandardWrapperValve.java:278)
WARNING: CORE3283: stderr:      at java.security.AccessController.doPrivileged(N
ative Method)
WARNING: CORE3283: stderr:      at org.apache.catalina.core.StandardWrapperValve
.invoke(StandardWrapperValve.java:274)
WARNING: CORE3283: stderr:      at org.apache.catalina.core.StandardPipeline.inv
oke(StandardPipeline.java:505)
WARNING: CORE3283: stderr:      at org.apache.catalina.core.StandardContextValve
.invoke(StandardContextValve.java:212)
WARNING: CORE3283: stderr:      at org.apache.catalina.core.StandardPipeline.inv
oke(StandardPipeline.java:505)
WARNING: CORE3283: stderr:      at org.apache.catalina.core.StandardHostValve.in
voke(StandardHostValve.java:203)
WARNING: CORE3283: stderr:      at org.apache.catalina.core.StandardPipeline.inv
oke(StandardPipeline.java:505)
WARNING: CORE3283: stderr:      at com.iplanet.ias.web.connector.nsapi.NSAPIProc
essor.process(NSAPIProcessor.java:158)
WARNING: CORE3283: stderr:      at com.iplanet.ias.web.WebContainer.service(WebC
ontainer.java:598)

Answer 6

你在执行了executeQuery之后没有关闭游标，导致游标积累过多。在你调用这个程序的页面中把游标关闭就可以了。rs.close();

Answer 7

只是把页面里的ResultSet对象都关闭就可以了吗？

Answer 8

把ResultSet对象都关闭了，可以还是不行啊！！！！！！！！！！！