Invoking Java in the Database

Giriş

Kendi kodumdan Stored Procedure çağrısı yaparak aslında bir Java kodunu çalıştırmak mümkün.

Örnek

Şöyle yaparız

CREATE OR REPLACE AND COMPILE JAVA SOURCE NAMED MYSCHEMA.JavaTools
AS 
package util.oracle;
import java.io.*;
import java.net.InetAddress;  
import java.util.List;

public class JavaTools {

  public static double pingOSCommand(String Command){
    double time = -1;
    try {
      Process process = Runtime.getRuntime().exec(Command);
      process.waitFor();
      BufferedReader stdInput = new BufferedReader(
        new InputStreamReader(process.getInputStream()));
      BufferedReader stdError = new BufferedReader(
        new InputStreamReader(process.getErrorStream()));
      while ((String s = stdInput.readLine()) != null) {
        if (s.contains("time=")) {
	  if (s.contains("ms")){
            time = Double.parseDouble(s.substring(s.indexOf("time=")+5,
              s.indexOf("ms")-1));
	  }
        }
      }
      while ((s = stdError.readLine()) != null) {
        System.out.println(s);
      }
      return time;
    } catch (Exception e){
      System.out.println(e.getMessage());
      return -1;
    } 
  }
};
/ 
/******************************************************************************/
GRANT EXECUTE ON JAVA SOURCE MYSCHEMA.RailwayJavaTools TO MYUSER;
COMMIT;

Execute dbms_java.grant_permission( 'MYUSER', 'SYS:java.io.FilePermission',
  '<<ALL FILES>>', 'execute');
execute dbms_java.grant_permission( 'MYUSER', 'SYS:java.lang.RuntimePermission',
  'writeFileDescriptor', '*' );
execute dbms_java.grant_permission( 'MYUSER', 'SYS:java.lang.RuntimePermission',
  'readFileDescriptor', '*' );
COMMIT;

Bunu çağırmak için şöyle yaparız. Sonuç olarak double döndürür

CREATE OR REPLACE PACKAGE MYSCHEMA.MyTools 
AS
  function f_pingOSCommand(command varchar2) return number;
END MyTools;
/

CREATE OR REPLACE PACKAGE body MYSCHEMA.MyTools
AS
  function f_pingOSCommand(command varchar2) 
  return number 
  as
  language java
  NAME 'util.oracle.JavaTools.pingOSCommand(java.lang.String) return double';
		
end MYTools;
/

Bunu çağırmak için şöyle yaparız. Sonuç olarak double döndürür

SELECT MYSCHEMA.MyTools.f_pingOSCommand(?) FROM DUAL