Java HashMap Key Set to String ,Array or Vector Convert: Use multiple type (String or Integer) data together as Key Value|| Procedure to retrieve (show) or get individual values from the multiple data type Hash Map key by splitting or breaking || next convert the key into vector.

The program given below will show you how to solve such situation.

Code Example:

import  java.util.Vector;

import java.util.HashMap;

import java.util.Set;

class HashMapKeyToVector

{

HashMap studentInfo=new HashMap();

public HashMapKeyToVector()

{

/*** following Roll and age will be used as key in the studentInfo HashMap **/

int student1Roll=10;

int student1age=11;

int student2Roll=12;

int student2age=13;

String  stdInfo1= student1Roll+”:”+student1age;

String  stdInfo2= student2Roll+”:”+student2age;

// Student Name is used to save data, or you can use any other vector

studentInfo.put(stdInfo1,”Adward”);

studentInfo.put(stdInfo2,”Rahim”);

/****************************************************/

System.out.println(“\n //Student Name as Value  and  Roll + Age  as  Key  in the HashMap \n”);

System.out.println(“1st Student Name = “+ studentInfo.get(stdInfo1)+ ” and Roll:Age as key = “+stdInfo1);

System.out.println(“2nd  Student Name = “+ studentInfo.get(stdInfo2)+ ” and  Roll:Age as key = “+stdInfo2);

//student

System.out.println(“\n  “);

Set key=studentInfo.keySet();

String[] strkeys =(String[]) key.toArray(new String[key.size()]);

Vector fullStudentInfo=new Vector();

System.out.println(“\n // Retrieving and Breaking  Keys (Roll+Age)  of  HashMap into individual Roll   and Key”);

System.out.println(“\n “);

for (int i=0;i<key.size();i++){

String[] result = strkeys[i].toString().split(“:”);

System.out.println(“Student  “+(i+1)+ ”  Roll is :”+result[0]+  ” and Age is :”+result[1] + ”  and Name is  : ” +studentInfo.get(strkeys[i].toString()));

//System.out.println(“\n “);

Vector  individualStudentInfo = new Vector();

individualStudentInfo.add(result[0]);

individualStudentInfo.add(result[1]);

individualStudentInfo.add(studentInfo.get(strkeys[i].toString()));

fullStudentInfo.add(individualStudentInfo);

}

System.out.println(“\n // Converting  HashMap Key  value  to Vector  “);

System.out.println(“\nAfter Entering into Vector  All student Info :”+fullStudentInfo);

}

public static void main(String args[])

{

HashMapKeyToVector x= new HashMapKeyToVector();

}

}