An article complete gist

GsonEx1.java

package in.ajduke.ap013;

import java.io.IOException;
import java.util.ArrayList;
import java.util.List;

import com.google.gson.Gson;
import com.google.gson.GsonBuilder;
import com.google.gson.annotations.SerializedName;

public class GsonEx1 {
  public static void main(String[] args) throws IOException {
		Gson gson = new Gson();
		String json = gson.toJson(new Developer());
		System.out.println("********* Compact mode ***********");
		System.out.println(json);

		GsonBuilder gsonBuilder = new GsonBuilder();
		Gson prettyGson = gsonBuilder.setPrettyPrinting().create();
		json = prettyGson.toJson(new Developer());
		System.out.println("\n ******* Pretty formatting *********");
		System.out.println(json);

	}
}

class Developer {
	private String classz;
	private String name;
	List<String> languagesKnown;

	public Developer() {
		name = "ajduke";
		languagesKnown = new ArrayList<>();
		languagesKnown.add("Java");
		languagesKnown.add("Scala");
		languagesKnown.add("Ruby");
	}
}

GsonEx2.java

package in.ajduke.ap013;

import java.io.IOException;
import java.util.ArrayList;
import java.util.List;

import com.google.gson.Gson;
import com.google.gson.GsonBuilder;

public class GsonEx {
  public static void main(String[] args) throws IOException {
		Gson gson = new Gson();
		String json;
		
		System.out.println("Default behaviour ");
		GsonBuilder gsonBuilder = new GsonBuilder();
		Gson prettyGson = gsonBuilder.setPrettyPrinting().create();
		json = prettyGson.toJson(new Developer());
		System.out.println(json);
		System.out.println("Including the nulls ");
		Gson includeNullsGson = gsonBuilder.serializeNulls().create();
		String json2 = includeNullsGson.toJson(new Developer());
		System.out.println(json2);
	}
}

class Developer {

	private String name;
	private String classz;
	List<String> languagesKnown;

	public Developer() {
		name = "ajduke";
		languagesKnown = new ArrayList<>();
		languagesKnown.add("Java");
		languagesKnown.add("Scala");
		languagesKnown.add("Ruby");
	}
}

GsonEx3.java

package in.ajduke.ap013;

import java.io.IOException;
import java.lang.reflect.Modifier;
import java.util.ArrayList;
import java.util.List;

import com.google.gson.Gson;
import com.google.gson.GsonBuilder;

public class GsonEx {
  public static void main(String[] args) throws IOException {
  	Gson gson = new Gson();

		System.out.println("Default behaviour ");
		GsonBuilder gsonBuilder = new GsonBuilder();
		Gson prettyGson = gsonBuilder.setPrettyPrinting().create();
	  String json = prettyGson.toJson(new Developer());
		System.out.println(json);

		System.out.println("Ignoring/excluding fields ");
		GsonBuilder excludeFieldsWithModifiers = gsonBuilder
				.excludeFieldsWithModifiers(Modifier.PRIVATE);
		Gson create = excludeFieldsWithModifiers.create();
		String json2 = create.toJson(new Developer());
		System.out.println(json2);
	}
}

class Developer {
	private String name;
	private String classz;
	List<String> languagesKnown;

	public Developer() {
		name = "ajduke";
		languagesKnown = new ArrayList<>();
		languagesKnown.add("Java");
		languagesKnown.add("Scala");
		languagesKnown.add("Ruby");
	}
}