在java中调用存储过程和存储函数
存储过程:
查询某个员工的姓名 月薪 职位:
create or replace procedure queryempinfo(eno in number,
pename out varchar2,
psal out number,
pjob out varchar2)
as
begin
select ename,sal,empjob into pename,psal,pjob from emp where empno=eno;
end;
存储函数:
--查询某个员工的年收入
create or replace function queryempincome(eno in number)
return number
as
--定义变量保存月薪和奖金
psal emp.sal%type;
pcomm emp.comm%type;
begin
select sal,comm into psal,pcomm from emp where empno=eno;
--返回年收入
return psal*12+nvl(pcomm,0);
end;
JDBCUtils:
package demo;
import java.sql.Connection;
import java.sql.DriverManager;
import java.sql.ResultSet;
import java.sql.SQLException;
import java.sql.Statement;
public class JDBCUtils {
private static String driver = "oracle.jdbc.OracleDriver";
private static String url = "jdbc:oracle:thin:@192.168.56.101:1521:orcl";
private static String user = "scott";
private static String password = "tiger";
static{
try {
Class.forName(driver);
} catch (ClassNotFoundException e) {
throw new ExceptionInInitializerError(e);
}
//DriverManager.registerDriver(driver)
}
public static Connection getConnection(){
try {
return DriverManager.getConnection(url, user, password);
} catch (SQLException e) {
e.printStackTrace();
}
return null;
}
/*
* 运行Java程序
* java -Xms100M -Xmx200M HelloWorld
*
* 技术方向:
* 1. 性能调优 ---> tomcat
* 2. 故障诊断 ---> 死锁
*/
public static void release(Connection conn,Statement st,ResultSet rs){
if(rs != null){
try {
rs.close();
} catch (SQLException e) {
e.printStackTrace();
}finally{
rs = null;// ----> java GC
}
}
if(st != null){
try {
st.close();
} catch (SQLException e) {
e.printStackTrace();
}finally{
st = null;
}
}
if(conn != null){
try {
conn.close();
} catch (SQLException e) {
e.printStackTrace();
}finally{
conn = null;
}
}
}
}
TestOracle:
package demo;
import java.sql.CallableStatement;
import java.sql.Connection;
import java.sql.ResultSet;
import oracle.jdbc.OracleCallableStatement;
import oracle.jdbc.OracleTypes;
import org.junit.Test;
public class TestOracle {
/*
* create or replace procedure queryempinfo(eno in number,
pename out varchar2,
psal out number,
pjob out varchar2)
*/
@Test
public void testProcedure(){
//{call [(,, ...)]}
String sql = "{call queryempinfo(?,?,?,?)}";
Connection conn = null;
CallableStatement call = null;
try {
conn = JDBCUtils.getConnection();
call = conn.prepareCall(sql);
//对于in参数,赋值
call.setInt(1, 7839);
//对于out参数,申明
call.registerOutParameter(2, OracleTypes.VARCHAR);
call.registerOutParameter(3, OracleTypes.NUMBER);
call.registerOutParameter(4, OracleTypes.VARCHAR);
//执行
call.execute();
//取出结果
String name = call.getString(2);
double sal = call.getDouble(3);
String job = call.getString(4);
System.out.println(name+"\t"+sal+"\t"+job);
} catch (Exception e) {
e.printStackTrace();
}finally{
JDBCUtils.release(conn, call, null);
}
}
/*
* create or replace function queryempincome(eno in number)
return number
*/
@Test
public void testFunction(){
//{?= call [(,, ...)]}
String sql = "{?=call queryempincome(?)}";
Connection conn = null;
CallableStatement call = null;
try {
conn = JDBCUtils.getConnection();
call = conn.prepareCall(sql);
//第一个是out参数
call.registerOutParameter(1, OracleTypes.NUMBER);
//第二个是in参数
call.setInt(2, 7839);
call.execute();
//取出年收入
double income = call.getDouble(1);
System.out.println(income);
} catch (Exception e) {
e.printStackTrace();
}finally{
JDBCUtils.release(conn, call, null);
}
}
}
在out参数中使用光标
查询某个部门中的所有员工信息 ---> 返回集合
包头
CREATE OR REPLACE PACKAGE MYPAKCAGE AS
type empcursor is ref cursor;
procedure queryEmpList(dno in number, empList out empcursor);
END MYPAKCAGE;
包体
CREATE OR REPLACE PACKAGE BODY MYPAKCAGE AS
procedure queryEmpList(dno in number, empList out empcursor) AS
BEGIN
open empList for select * from emp where deptno=dno;
END queryEmpList;
END MYPAKCAGE;
java代码:
@Test
public void testCursor(){
String sql = "{call MYPAKCAGE.queryEmpList(?,?)}";
Connection conn = null;
CallableStatement call = null;
ResultSet rs = null;
try {
conn = JDBCUtils.getConnection();
call = conn.prepareCall(sql);
//对于in参数,赋值
call.setInt(1, 20);
//对于out参数 申明
call.registerOutParameter(2, OracleTypes.CURSOR);
call.execute();
//取出结果
rs = ((OracleCallableStatement)call).getCursor(2);
while(rs.next()){
//取出一个员工
String name = rs.getString("ename");
double sal = rs.getDouble("sal");
System.out.println(name+"\t"+sal);
}
} catch (Exception e) {
e.printStackTrace();
}finally{
JDBCUtils.release(conn, call, rs);
}
}
光标在JDBCUtils.release(conn, call, rs);语句中被关闭。