Question

java 连接firebird 数据库，执行完代码后链接不释放，求大神解答下，在线等

public void updatesql(String username,String password,String sql){
org.firebirdsql.pool.FBWrappingDataSource dataSource =
new org.firebirdsql.pool.FBWrappingDataSource();
dataSource.setDatabase ("localhost/3050:D:/Program Files/Firebird/Firebird_2_5/db/SECURITY_SENSEDATA2.FDB");
dataSource.setDescription ("dbconnect func");
dataSource.setType("TYPE4");
dataSource.setEncoding("ISO8859_1");
java.sql.Statement stat=null;
java.sql.Connection conn=null;
try {
dataSource.setLoginTimeout (10);
conn = dataSource.getConnection (username, password);
stat = conn.createStatement();
System.out.println("establisted: "+stat);
String sqlstr=sql;
stat.executeUpdate(sqlstr);

stat.close();
conn.close();
}
catch(java.sql.SQLException e) {
e.printStackTrace();
System.out.println ("sql exception: " + e.getMessage ());
}
}
执行完conn.close()之后，在数据库查看 用户还是处于登录状态，我每个文件都会执行这个代码一次，几百次之后，系统就挂掉了，报类似的错误：
at org.firebirdsql.jdbc.AbstractStatement.checkValidity(AbstractStatement.java:1522)
at org.firebirdsql.jdbc.AbstractStatement.executeUpdate(AbstractStatement.java:269)
at sun.reflect.GeneratedMethodAccessor5.invoke(Unknown Source)
at sun.reflect.DelegatingMethodAccessorImpl.invoke(DelegatingMethodAccessorImpl.java:43)
at java.lang.reflect.Method.invoke(Method.java:601)
at org.firebirdsql.pool.StatementHandler.invoke(StatementHandler.java:107)
at $Proxy1.executeUpdate(Unknown Source)
at security.filebirdconn.updatesql(filebirdconn.java:56)
at security.filtcsvfile.filtfiledb(filtcsvfile.java:114)
at security.filtcsvfile.filtfile(filtcsvfile.java:178)
at security.filtcsvfile.main(filtcsvfile.java:206)

Answer 1

不能这么写， 在关闭连接之前先得判断这个连接是什么状态！