First Non Null 

Google Guava is a java library with lot of utilities and reusable components. This requires the library guava-10.0.jar to be in classpath. The following example shows using Objects.firstNonNull() API. It returns the first non null parameter of the given two parameters and throws NullPointerException if both parameters are null.

File Name  :   com/bethecoder/tutorials/guava/base_tests/FirstNonNullTest.java  Author  :   Sudhakar KV Email  :   [email protected]

package com.bethecoder.tutorials.guava.base_tests; import com.google.common.base.Objects; public class FirstNonNullTest {   /**    * @param args    */   public static void main(String[] args) {          String value = Objects.firstNonNull(System.getProperty("java.home"), "C:\\Java\\jdk1.6.0");     System.out.println(value);          value = Objects.firstNonNull(System.getProperty("java.home2"), "C:\\Java\\jdk1.6.0");     System.out.println(value);          try {       value = Objects.firstNonNull(System.getProperty("java.home2"), null);       System.out.println(value);     } catch (NullPointerException e) {       System.out.println("Both parameters are nulls");     }   } }

C:\Program Files\Java\jdk1.6.0_10\jre
C:\Java\jdk1.6.0
Both parameters are nulls