Call java from PL/SQL

1. Create file java

public class Hello
{
  public static String world()
  {
    return "Hello world";
  }
}

2. Complier file java 

Javac Hello.java

3. Loadjava to database 

C:\app\shbadmin\product\11.2.0\client_1\BIN>loadjava -r -user xxx@xxx d:
\Hello.class

4.Create function database 

 CREATE OR REPLACE FUNCTION helloworld RETURN VARCHAR2 AS
 LANGUAGE JAVA NAME 'Hello.world () return java.lang.String';

5 . Result:

select helloworld() from dual;


Note: Version javac and loadjava the same if different  error : \

java.lang.UnsupportedClassVersionError