如何在out参数中调用带有Char的Oracle存储过程？

Question

需要帮助。我试图从java调用pl / sql函数。 pl / sql函数将IN OUT CHAR参数作为参数之一。我只发送一个字符并将该char值分配给临时char值。但是得到pl / sql数值错误，进一步调试显示参数的长度如32767.无法得到如何解决它。我使用Oracle 12c db和ojdbc7.jar连接到它。下面是java代码和PL / SqL代码。

import java.sql.Connection;
import java.sql.DriverManager;
import java.sql.Types;



public class TestInOutParam {

public static void main(String[] args){
    try{
        Class.forName("oracle.jdbc.driver.OracleDriver");  
        Connection con=DriverManager.getConnection("jdbc:oracle:thin:@ragh:1521:inst1","schema1","schema1");




        OracleCallableStatement procCall = (OracleCallableStatement)con.prepareCall("{? = call TEMPPROC (?,?,?,?)}");

        String a = "ragh";
        String b="n";
        Integer c = 50;


        procCall.registerOutParameter(1, Types.INTEGER);
        procCall.registerOutParameter(2, Types.VARCHAR);
        procCall.registerOutParameter(3, Types.CHAR, 0, 1);
        procCall.registerOutParameter(4, Types.INTEGER);
        procCall.registerOutParameter(5, Types.DATE);

        procCall.setString(2, a);
        procCall.setString(3, b);
        procCall.setInt(4, c);
        procCall.setDate(5, getCurrentDate());



        procCall.executeUpdate();

    }catch(Exception e){ System.out.println(e);}
    }

private static java.sql.Date getCurrentDate() {
    java.util.Date today = new java.util.Date();
    return new java.sql.Date(today.getTime());
}

}

下面是PL / SQL代码，

CREATE TABLE TEMP
(
 MSG  VARCHAR2(3000 BYTE),
 DT   DATE
 )
 /

 CREATE OR REPLACE function tempproc(a in out varchar, b in out char, c in            out integer, d in out date) return integer
 is
    errm varchar2(3000);
    tempb char(32);
    tempa varchar2(10);
    tempc integer;
    tempd date;
    result integer;
    begin

tempa := a;
insert into temp values('varchar value'||tempa, sysdate); commit;
tempc := c;
insert into temp values('integer value'||tempc, sysdate); commit;
tempd := d;
insert into temp values('date value', tempd); commit;
tempb := b;
insert into temp values('char value'||tempb, sysdate); commit;
commit;
return result;
 exception 
when others then
errm := sqlerrm;
 insert into temp values ('ex'||errm, sysdate);
 commit;
return 2;
end;
 /