gistfile1.txt

/*Activity */
package jiran.com.myapplication;

import android.support.v7.app.AppCompatActivity;
import android.os.Bundle;
import android.util.Log;

import io.realm.Realm;

public class MainActivity extends AppCompatActivity {

	Realm mRealm;
	@Override
	protected void onCreate(Bundle savedInstanceState) {
		super.onCreate(savedInstanceState);
		setContentView(R.layout.activity_main);
		mRealm = Realm.getDefaultInstance();
		mRealm.executeTransactionAsync(new Realm.Transaction() {
			@Override
			public void execute(Realm realm) {
				realm_test realm_test = realm.createObject(realm_test.class);
				realm_test.setId("1");
				realm_test.setLogin_id("2");
			}
		}, new Realm.Transaction.OnSuccess() {
			@Override
			public void onSuccess() {
				Log.d("AA", "onSuccess: ");
			}
		}, new Realm.Transaction.OnError() {
			@Override
			public void onError(Throwable error) {
				error.printStackTrace();
			}
		});
	}
}

gistfile2.txt

/*realm Object */
package jiran.com.myapplication;

import io.realm.RealmObject;
import io.realm.annotations.PrimaryKey;

/**
 * Created by user on 2016-07-19.
 */
public class realm_test extends RealmObject {
	@PrimaryKey
	private String id;
	private String login_id;

	public String getLogin_id() {
		return login_id;
	}

	public void setLogin_id(String login_id) {
		this.login_id = login_id;
	}

	public String getId() {

		return id;
	}

	public void setId(String id) {
		this.id = id;
	}
}

test_realm

/*Application*/
package jiran.com.myapplication;

import android.app.Application;

import io.realm.Realm;
import io.realm.RealmConfiguration;

public class MyApplication extends Application {
	private static MyApplication sInstance;

	public MyApplication() {
		sInstance = this;
	}

	public static synchronized MyApplication getInstance() {
		return sInstance;
	}

	@Override
	public void onCreate() {
		super.onCreate();
		RealmConfiguration config = new RealmConfiguration.Builder(this)
                .deleteRealmIfMigrationNeeded()
				.schemaVersion(0)
				.build();
		Realm.setDefaultConfiguration(config);

	}
}