Playing Around With Frequently Changing String Tokenizer

Playing Around With Frequently Changing String Tokenizer

Recently I was working on one of my Project Module. I had to use some data from the other module and they were sending this in the form of String Tokens, like "element_1;element_2;element_3;element_4;". So, as normal I did the normal tokenize code and break this tokens to use the values. Now they changed the token order, so I would have to do all the rework.

After that I came up with some solutions so that my code rework can be minimised even if the  token orders are changed. So I did the following:

1) Add all the tokens in the List. Let’s say, in the tokenizer parser method, just add all the token in the List.

2) Do not write any core logic in the token parser method.

3) Now create a enum or any such structure which will hold the token position. In my case I use the enum.

                e.g.

public enum ElementPositionEnum {

       ELEMENT_1(0), ELEMENT_2(1), ELEMENT_3(2), ELEMENT_4(3);

       private int position;

       ElementPositionEnum(int position) {

              this.position = position;

       }

       public int getPosition() {

              return this.position;

      }

}

4) Now while creating the object or setting the value to my object, just fetch the elements from the List based upon the Enum position.

                E.g. If I have to fetch the value,  I will do it like this:

                String myVal = List.get(MyElementPositionEnum.ELEMENT_1.getPosition());

5) So, even if the tokens sequence is changed, then  we only need to change the enum's value. Rest of the code will be same.

Java Code for Same :

public class TokenizerParser {

       public TokenElementTO parseToken(String token)

       {

              List listOfTOken = new ArrayList();

              String[] tokens = token.split(";");

              for(String val : tokens)

              {

                     listOfTOken.add(val);

              }

              return createTokenElementObject(listOfTOken);

       }

        private TokenElementTO createTokenElementObject(List listOfTOken)           {

              TokenElementTO to = new TokenElementTO();

              if(listOfTOken.size() > ElementPositionEnum.ELEMENT_1.getPosition())

                     to.setElement_1(listOfTOken.getElementPositionEnum.ELEMENT_1.getPosition()));

              if(listOfTOken.size() > ElementPositionEnum.ELEMENT_2.getPosition())

                     to.setElement_2(listOfTOken.get(ElementPositionEnum.ELEMENT_2.getPosition()));

              if(listOfTOken.size() > ElementPositionEnum.ELEMENT_3.getPosition())

                     to.setElement_3(listOfTOken.get(ElementPositionEnum.ELEMENT_3.getPosition()));

              if(listOfTOken.size() > ElementPositionEnum.ELEMENT_4.getPosition())

                     to.setElement_4(listOfTOken.get(ElementPositionEnum.ELEMENT_4.getPosition()));

               return to;

       }

 

       public static void main(String[] args)

       {

              TokenizerParser main = new TokenizerParser();

              String tokens = "AAA;BBB;CCC;DDDD";

              main.parseToken(tokens);

       }

}

 

public class TokenElementTO {

 

       private String element_1;

       private String element_2;

       private String element_3;

       private String element_4;

 

       public String getElement_1() {

              return element_1;

       }

       public void setElement_1(String element_1) {

              this.element_1 = element_1;

       }

       public String getElement_2() {

              return element_2;

       }

       public void setElement_2(String element_2) {

              this.element_2 = element_2;

       }

       public String getElement_3() {

              return element_3;

       }

       public void setElement_3(String element_3) {

              this.element_3 = element_3;

       }

       public String getElement_4() {

              return element_4;

       }

       public void setElement_4(String element_4) {

              this.element_4 = element_4;

       }

}