System.getProperties().put("http.proxyHost","someProxyURL");System.getProperties().put("http.proxyPort","someProxyPort");System.getProperties().put("http.proxyUser","someUserName");System.getProperties().put("http.proxyPassword","somePassword");

　　System.getProperties().put("http.proxyHost","someProxyURL");System.getProperties().put("http.proxyPort","someProxyPort");System.getProperties().put("http.proxyUser","someUserName");System.getProperties().put("http.proxyPassword","somePassword");12.Java Singleton exampleRead this article formore details.Update:Thanks Markus for the comment. I have updatedthe code and changedit to

　　more robust implementation.

　　public class SimpleSingleton private staticSimpleSingletonsingleInstance = new SimpleSingleton(); //Markingdefaultconstructor private //to avoid direct instantiation.privateSimpleSingleton() //Get instance for class SimpleSingletonpublicstatic SimpleSingleton getInstance() returnsingleInstance;

　　public class SimpleSingleton private staticSimpleSingletonsingleInstance = new SimpleSingleton();

　　//Marking default constructor private//to avoiddirectinstantiation.private SimpleSingleton()

　　//Get instance for class SimpleSingletonpublicstaticSimpleSingleton getInstance()

　　return singleInstance;One more implementation of Singletonclass.Thanks to Ralph and Lukasz Zielinski

　　for pointing this out.

　　public enum SimpleSingleton INSTANCE; publicvoiddoSomething()//Call the method fromSingleton:SimpleSingleton.INSTANCE.doSomething();

　　public enum SimpleSingleton INSTANCE;public voiddoSomething()

　　//Call the methodfromSingleton:SimpleSingleton.INSTANCE.doSomething();