?? db.java
字號:
package huc.blog.util;
import java.sql.Connection;
import javax.naming.Context;
import javax.naming.InitialContext;
import javax.naming.NamingException;
import javax.sql.DataSource;
public class DB {
private Connection conn = null;
private DataSource ds = null;
private String jdbcName = "jdbc/blog";
private Context ctx = null;
private StringBuffer jdbcStr = new StringBuffer();
public DB(){
jdbcStr.append("java:comp/env/");
jdbcStr.append(this.jdbcName);
this.init();
}
public DB(String jdbcName){
jdbcStr.append("java:comp/env/");
jdbcStr.append(jdbcName);
this.init();
}
/**
* 獲得打開的Connection
*
* @return
*/
public Connection getConnection() {
try {
conn = ds.getConnection();
} catch (Exception e) {
System.out.println("connect db error:" + e.getMessage());
return null;
}
return conn;
}
/**
* 初始化ctx和ds
*
*/
public void init(){
try {
ctx = new InitialContext();
if (ctx == null)
throw new Exception("沒有匹配的環境");
ds = (DataSource) ctx.lookup(jdbcStr.toString());
if (ds == null)
throw new Exception("沒有匹配數據庫");
} catch (NamingException e) {
e.printStackTrace();
} catch (Exception e) {
e.printStackTrace();
}
}
}
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