Trove Collection : Procedure & Function

• GNU provides a  collection API for Java for high performance.

• We can implement some collection interface to customize our own requirement.

• We can create procedure and function on each object of the collection.

• Download Link of Trove Library:-

           http://sourceforge.net/projects/trove4j/files/

Project Structure:-

Trove HashMap (Procedure & Function):-

Create a Object Procedure:-

• To create a Procedure we need to override TObjectProcedure interface.

        MyObjectProcedure.java

package com.sandeep.trove.collection;

import gnu.trove.procedure.TObjectProcedure;

public class MyObjectProcedure implements TObjectProcedure{

 /*
  *This method returns boolean 
  * false :-  procedure is called only once
  * true :- procedure is called for each value 
  */
 @Override
 public boolean execute(String objvalue) {
  
  System.out.println("Length of "+objvalue+" is : "+objvalue.length());
  
  return true;
 }

}

Create a Object Function:-

MyObjectFunction.java

package com.sandeep.trove.collection;

import gnu.trove.function.TObjectFunction;

public class MyObjectFunction implements TObjectFunction {

 @Override
 public String execute(String object) {
  return "My Name : " + object;
 }

}

Using Procedure & Function :-

package com.sandeep.trove.collection;

import gnu.trove.map.TMap;
import gnu.trove.map.hash.THashMap;

public class GnuTroveDemo {

 
 public static void main(String[] args) {

  TMap trovemap = new THashMap(); 
  trovemap.put("Key1", "Sangeeta");
  trovemap.put("Key2", "Surabhi");
  
  System.out.println("Original Value of Trove Map");
  for(String aValue: trovemap.values()){
   
   System.out.print(aValue+"n");
  }
  
  /*Trove Procedure is called on each object*/
  System.out.println("Procedure Called :- ");
  trovemap.forEachValue(new MyObjectProcedure());
  
  
  /*Trove Function is called on each value to manipulate it*/
  System.out.println("Function Called :- ");
  trovemap.transformValues(new MyObjectFunction());
  
   for(String aValue: trovemap.values()){
   
   System.out.println(aValue);
  }
  
 }

}

Output:-

Original Value of Trove Map
Surabhi
Sangeeta
Procedure is Called :-
Length of Surabhi is : 7
Length of Sangeeta is : 8
Function Called :-
My Name : Surabhi
My Name : Sangeeta

Code Download Link:-

downlod trove demo