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package com;
import java.sql.*;
import javax.sql.*;
public class Test {
public static void main(String[] args){
Connection conn = null;
Statement stmt = null;
ResultSet rs = null;
//1。注册驱动
try {
Class.forName("oracle.jdbc.driver.OracleDriver");
//2。通过驱动管理器建立连接
String url = "jdbc:oracle:thin:@192.168.0.106:1521:dylanfire";
String dbUsername = "scott";
String dbPassword = "dylan";
conn = DriverManager.getConnection(url, dbUsername, dbPassword);
//3.建立连接对象
stmt = conn.createStatement();
//4、通过对象传递数据，并返回结果
String sql = "select ename, job, sal, hiredate from emp";
rs = stmt.executeQuery(sql);
while(rs.next()){
String ename = rs.getString("ename");
String job = rs.getString("job");
Double sal = rs.getDouble("sal");
java.sql.Date hiredate = rs.getDate("hiredate");
System.out.println(ename + ", " + job + ", " + sal + ", " + hiredate);
}
} catch (ClassNotFoundException e) {
// TODO Auto-generated catch block
e.printStackTrace();
} catch (SQLException e) {
// TODO Auto-generated catch block
e.printStackTrace();
} finally{
try {
rs.close();
} catch (SQLException e) {
// TODO Auto-generated catch block
e.printStackTrace();
}
try {
stmt.close();
} catch (SQLException e) {
// TODO Auto-generated catch block
e.printStackTrace();
}
try {
conn.close();
} catch (SQLException e) {
// TODO Auto-generated catch block
e.printStackTrace();
}
}
}
}
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oracle服务器的server-name是dylanfire
192.168.0.106是局域网安装oracle数据库的IP。
我通过telnet可以访问到oracle的数据库
不知道为什么通过JAVA就不可以
eclipse给出的异常为：
java.sql.SQLException: The Network Adapter could not establish the connection
at oracle.jdbc.driver.T4CConnection.logon(T4CConnection.java:451)
at oracle.jdbc.driver.PhysicalConnection.<init>(PhysicalConnection.java:535)
at oracle.jdbc.driver.T4CConnection.<init>(T4CConnection.java:218)
at oracle.jdbc.driver.T4CDriverExtension.getConnection(T4CDriverExtension.java:29)
at oracle.jdbc.driver.OracleDriver.connect(OracleDriver.java:528)
at java.sql.DriverManager.getConnection(Unknown Source)
at java.sql.DriverManager.getConnection(Unknown Source)
at com.Test.main(Test.java:21)
Caused by: oracle.net.ns.NetException: The Network Adapter could not establish the connection
at oracle.net.nt.ConnStrategy.execute(ConnStrategy.java:356)
at oracle.net.resolver.AddrResolution.resolveAndExecute(AddrResolution.java:419)
at oracle.net.ns.NSProtocol.establishConnection(NSProtocol.java:811)
at oracle.net.ns.NSProtocol.connect(NSProtocol.java:249)
at oracle.jdbc.driver.T4CConnection.connect(T4CConnection.java:1407)
at oracle.jdbc.driver.T4CConnection.logon(T4CConnection.java:328)
... 7 more
Caused by: java.net.ConnectException: Connection refused: connect
at java.net.TwoStacksPlainSocketImpl.socketConnect(Native Method)
at java.net.AbstractPlainSocketImpl.doConnect(Unknown Source)
at java.net.AbstractPlainSocketImpl.connectToAddress(Unknown Source)
at java.net.AbstractPlainSocketImpl.connect(Unknown Source)
at java.net.PlainSocketImpl.connect(Unknown Source)
at java.net.SocksSocketImpl.connect(Unknown Source)
at java.net.Socket.connect(Unknown Source)
at oracle.net.nt.TcpNTAdapter.connect(TcpNTAdapter.java:138)
at oracle.net.nt.ConnOption.connect(ConnOption.java:120)
at oracle.net.nt.ConnStrategy.execute(ConnStrategy.java:334)
... 12 more
Exception in thread "main" java.lang.NullPointerException
at com.Test.main(Test.java:44)
希望各位大侠帮我看看。有什么可能出现这种问题的情况
我一个一个的排查
地址url不对:具体ip的话去掉@，localhost前加@
String url = "jdbc:oracle:thin:@localhost:1521:ORCL";// 127.0.0.1是本机地址，XE是精简版Oracle的默认数据库名
// String url = "jdbc:oracle:thin:192.168.0.167:1521:ORCL";// 127.0.0.1是本机地址，XE是精简版Oracle的默认数据库名 |