Parse and write JSON data in Java with Gson

Here i am showing you full examples of using following Gson streaming APIs to read and write JSON data.

As a pre-requisite, you are required to download the gson-2.1.jar

Create A GetJson.java class as bellow.

public class GetJson {

   public static void main(String args[]){

   GetJson  obj= new GetJson(); 

   obj.getJsonData();

   } 

   public void getJsonData(){

   

   //[{amount":9283.41,"balanceAfterTransaction":9283.41,"bank":"Bank_0160021000998","category":"OPENING_BALANCE","dateTime":"01/05/2017","description":"OPENING BALANCE","remark":null,"transactionNumber":null,"type":"CREDIT","valueDate":null},{"amount":100000.0,"balanceAfterTransaction":109283.41,"bank":"Bank_01698210009909","category":"OTHER","dateTime":"01/05/2017","description":" BY INST 51 : CTO12- 1 DAY LAT","remark":null,"transactionNumber":"KZT2","type":"CREDIT","valueDate":null}]    

   String inputLine = "[{amount\":9283.41,\"balanceAfterTransaction\":9283.41,\"bank\":\"Bank_0160021000998\",\"category\":\"OPENING_BALANCE\",\"dateTime\":\"01/05/2017\",\"description\":\"OPENING BALANCE\",\"remark\":null,\"transactionNumber\":\"trx009\",\"type\":\"CREDIT\",\"valueDate\":null},{\"amount\":100000.0,\"balanceAfterTransaction\":109283.41,\"bank\":\"Bank_01698210009909\",\"category\":\"OTHER\",\"dateTime\":\"01/05/2017\",\"description\":\" BY INST 51 : CTO12- 1 DAY LAT\",\"remark\":null,\"transactionNumber\":\"KZT2\",\"type\":\"CREDIT\",\"valueDate\":null}]";    

   String jsonData = "{\"bankTransactionList\":"+inputLine+"}";

   int sizeList =0;

    String amount =null;

String balanceAfterTransaction =null;

String bank =null;

String category = null;

String dateTime = null;

String description = null;

String remark = null;

String transactionNumber = null;

String type = null;

String valueDate = null;

   try{

   Gson gson = new Gson();

   BankArrayList myData = gson.fromJson(jsonData, BankArrayList.class);

   System.out.println("myDataList size >> "+myData.bankTransactionList.size());

   sizeList = myData.bankTransactionList.size();

   for(int i=0;i<sizeList;i++){

   System.out.println("Amount >> "+ myData.bankTransactionList.get(i).amount);

   System.out.println("balanceAfterTransaction >> "+ myData.bankTransactionList.get(i).balanceAfterTransaction);

   System.out.println("bank >> "+ myData.bankTransactionList.get(i).bank);

   System.out.println("dateTime >> "+ myData.bankTransactionList.get(i).dateTime);

   System.out.println("description >> "+ myData.bankTransactionList.get(i).description);

   System.out.println("transactionNumber >> "+ myData.bankTransactionList.get(i).transactionNumber);

   System.out.println("type >> "+ myData.bankTransactionList.get(i).type);

   System.out.println("valueDate >> "+ myData.bankTransactionList.get(i).valueDate);

   System.out.println("--------------------------------------------------------");

   

   }

   

   }catch(Exception ex){

  ex.printStackTrace(); 

   }

   }

}

Create A Bank.java class as bellow.

public class Bank {

public String amount;

public String balanceAfterTransaction;

public String bank;

public String category;

public String dateTime;

public String description;

public String remark;

public String transactionNumber;

public String type;

public String valueDate;

}

Create A BankArrayList.java class as bellow.

public class BankArrayList {

public ArrayList<Bank> bankTransactionList = new ArrayList <Bank>();

}

After run GetJson.java file, Result will be display as bellow image