java代码连接到oracle数据库

package com.deng.oracle;
import java.sql.Connection;
import java.sql.DriverManager;
import java.sql.ResultSet;
import java.sql.SQLException;
import java.sql.Statement;
public class TestOracle {
public static void main(String[] args) {
try {
Class.forName("oracle.jdbc.driver.OracleDriver");
//System.out.println("有数据库驱动");
String url = "jdbc:oracle:thin:@127.0.0.1:1521:orcl";
Connection conn;
try {
conn = DriverManager.getConnection(url, "scott", "tiger");
Statement stmt = conn.createStatement();
String sql = "select * from emp";
ResultSet rs = stmt.executeQuery(sql);
while (rs.next()) {
System.out.println("ENAME: " + rs.getString(2));
}
} catch (SQLException e) {
e.printStackTrace();
}
} catch (ClassNotFoundException e) {
e.printStackTrace();
}
}
}

首先, 在classpath环境变量下加载oracle的数据库驱动: classes12.jar或者是ojdbc14.jar, 然后加载各个SQL的类, 编写url, 这个url是jdbc:oracle:thin:@127.0.0.1:1521:orcl, 其中1521是端口号, orcl是数据库的SID, 这个SID可以在注册表中查看得到, cmdà regedit, 在注册表中HKEY_LOCAL_MACHINE\SOFTWARE\ORACLE\HOME0键值ORACLE_SID可以看到这个SID: orcl.