java调用oracle函数的问题[急求]

oracle代码：
Create or REPLACE FUNCTION AAAAA (
    P_USER_ID_I  IN  VARCHAR2 
)
RETURN  SYS_REFCURSOR
AS
    P_RESULT_SET_O  SYS_REFCURSOR;
    X_SQL VARCHAR2(200);
BEGIN
    X_SQL :='select user_id,user_name,email from user_mst where user_id like ''%' || P_USER_ID_I ||'%''';
    OPEN P_RESULT_SET_O FOR X_SQL;
    RETURN P_RESULT_SET_O; 
END AAAAA;

java调用代码：
                        Class.forName("oracle.jdbc.driver.OracleDriver");
conn = DriverManager.getConnection((new StringBuilder(
"jdbc:oracle:thin:@")).append("127.0.0.1").append(":")
.append("1522").append(":").append("ORCL").toString(),
"system", "123456");
cstmt = conn.prepareCall("{? = call AAAAA(?)}");
cstmt.setString(2, "mb2");
cstmt.registerOutParameter(1, oracle.jdbc.OracleTypes.CURSOR);

cstmt.execute();
rs = (ResultSet) cstmt.getObject(1);
if (rs != null) {
System.out.print("user_id");
System.out.print(" user_name");
System.out.print(" email