-- 判断用户从键盘输入的数字并打印相应语句
-- 接收键盘输入
-- accept addr prompt ‘xxx‘
-- addr 是一个地址值，在该地址上保持了输入的值
accept num prompt ‘请输入一个数字‘;
declare 
  pnum number := #
  -- 注意：取出存在在这个地址值的值要使用‘&‘符号相当于c的指针
begin
  if pnum = 0 then dbms_output.put_line(‘you input 0‘);
     else if pnum = 1 then dbms_output.put_line(‘you input 1‘);
     else then dbms_output.put_line(‘you input other number‘);
     end if;
end;

declare
  --部门
  cursor cdept is select deptno from dept;
  pdeptno dept.deptno%type;
  
  --部门中员工的薪水
  cursor cemp(dno number) is select sal from emp where deptno=dno;
  psal emp.sal%type;
  
  --每个段的人数
  count1 number; count2 number; count3 number;
  --部门的工资总额
  salTotal number := 0;
begin
  --部门
  open cdept;
  loop
       --取一个部门
       fetch cdept into pdeptno;
       exit when cdept%notfound;
       
       --初始化
       count1:=0; count2:=0; count3:=0;
       --得到部门的工资总额
       select sum(sal) into salTotal  from emp where deptno=pdeptno;
       
       --取部门的中员工薪水
       open cemp(pdeptno);
       loop
            --取一个员工的薪水
            fetch cemp into psal;
            exit when cemp%notfound;
            
            --判断
            if psal < 3000 then count1:=count1+1;
               elsif psal >=3000 and psal<6000 then count2:=count2+1;
               else count3:=count3+1;
            end if;
       end loop;
       close cemp;

       --保存结果
       insert into msg values(pdeptno,count1,count2,count3,nvl(saltotal,0));

  end loop;
  close cdept;
  
  commit;
  dbms_output.put_line(‘完成‘);
  
end;

package demo;

import java.sql.*;

public class JDBCUtils {
    private static String driver = "oracle.jdbc.OracleDriver";
    private static String url = "jdbc:oracle:thin:@169.254.35.157:1521/orcl";
    private static String user = "scott";
    private static String password = "tiger";

    static{
        // 注册驱动
        try {
            Class.forName(driver);
        } catch (ClassNotFoundException e) {
            throw new ExceptionInInitializerError(e);
        }
    }

    public static Connection getConnection() {
        try {
            return DriverManager.getConnection(url, user, password);
        } catch (SQLException e) {
            e.printStackTrace();
        }
        return null;
    }

    public static void release(Connection conn, Statement st, ResultSet rs) {
        if (rs != null) {
            try {
                rs.close();
            } catch (SQLException e) {
                e.printStackTrace();
            }
            finally{
                rs = null;
                // 置空作为垃圾回收
            }
        }
        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;
            }
        }
    }
}

 /*
    procedure queryEmpInformation(eno in number,
                                  pename out varchar2,
                                  psal   out number,
                                  pjob   out varchar2)
                                  */
    @Test
    public void testProcedure() {
        String sql = "{call queryEmpInformation(?,?,?,?)}";
        Connection conn = null;
        CallableStatement call = null;
        try {
            conn = JDBCUtils.getConnection();
            call = conn.prepareCall(sql);

            // 对于in参数，需要对其赋值
            call.setInt(1, 7839);

            // 对于out参数，需要对其声明
            call.registerOutParameter(2, OracleTypes.VARCHAR);
            call.registerOutParameter(3, OracleTypes.NUMBER);
            call.registerOutParameter(4, OracleTypes.VARCHAR);

            // 执行调用存储过程
            call.execute();

            // 从CallableStatement对象中取出输出out参数
            String name = call.getString(2);
            Double sal = call.getDouble(3);
            String job = call.getString(4);

            System.out.println("name:" + name + " sal:" + sal + " job:" + job);

        } catch (SQLException e) {
            e.printStackTrace();
        } finally {
            JDBCUtils.release(conn, call, null);
        }

    }

    /*
    function queryEmpIncome(eno in number)
    return number
    */
    @Test
    public void testFunction() {
        String sql = "{?= call queryEmpIncome(?)}";
        Connection conn = null;
        CallableStatement call = null;
        try {
            conn = JDBCUtils.getConnection();
            call = conn.prepareCall(sql);

            // 存储函数的输出参数即返回值，是第一个问号，对其注册
            call.registerOutParameter(1, OracleTypes.NUMBER);

            // 赋值输入参数
            call.setInt(2, 7839);

            call.execute();

            double annIncome = call.getDouble(1);

            System.out.println("annual income:" + annIncome);

        } catch (SQLException e) {
            e.printStackTrace();
        } finally {
            JDBCUtils.release(conn, call, null);
        }
    }

    @Test
    public void testCursor() {
        String sql = "{call mypackage.queryemplist(?,?)}";
        Connection conn = null;
        CallableStatement call = null;
        try {
            conn = JDBCUtils.getConnection();
            call = conn.prepareCall(sql);

            call.setInt(1, 10);

            call.registerOutParameter(2, OracleTypes.CURSOR);

            call.execute();

            // CallableStatement是一个通用的接口，获取时获得Oracle适用的实现类对象，可以将其强制转换成Oracle适用的接口
            ResultSet cursor = ((OracleCallableStatement) call).getCursor(2);

            while (cursor.next()) {
                System.out.println("name:"+cursor.getString("ename"));
                System.out.println("hiredate:"+cursor.getDate("hiredate"));
            }


        } catch (SQLException e) {
            e.printStackTrace();
        } finally {
            JDBCUtils.release(conn, call, cursor);
            // 此处关闭ResultSet时同时关闭了这个光标
        }
    }