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References and Resources java  1.  Java General Java mother site @  http://java.sun.com  (or  http://www.oracle.com/technetwork/java/index.html ). Java Developers' sites, in particular,  http://java.net . JDK  (aka  Java SE ) Java SE  mother site @  http://java.sun.com/javase  (or  http://www.oracle.com/technetwork/java/javase/overview/index.html ). JDK 7  API  Documentation Online @  http://download.oracle.com/javase/7/docs/api/index.html . JDK 7 Documentation Online @  http://download.oracle.com/javase/7/docs/ . Ken Arnold, James Gosling and David Holmes, "The Java Programming Language", 4th ed, 2005. (The defacto standard for Java Language, but does not seem to have been updated to cover the latest features?!) James Gosling, Bill Joy, Guy Steele and Gilad Bracha, "The Java Language Specification", 3rd ed, 2005. (The defacto standard for JVM, but does not seem to have been updated?!)...
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What is string immutability?

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What is string immutability? Here are a set of diagrams to illustrate Java String's  immutability . 1. Declare a string String s = "abcd" ; s stores the reference of the string object. The arrow below should be interpreted as "store reference of". 2. Assign one string variable to another string variable String s2 = s ; s2 stores the same reference value, since it is the same string object. 3. Concat string s = s. concat ( "ef" ) ; s now stores the reference of newly created string object. Summary Once a string is created in  memory (heap), it can not be changed. We should note that all methods of String do not change the string itself, but rather return a new String. If we need a string that can be modified, we will need StringBuffer or StringBuilder. Otherwise, there would be a lot of time wasted for Garbage Collection, since each time a new String is created.  Here  is an example of StringBuilder u...
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Java Question ..............? Q1. What is a cookie ? Ans. A cookie is a small piece of text stored on a user's computer by the browser for a specific domain. Commonly used for authentication, storing site preferences, and server session identification. Q2. Can we reduce the visibility of the overridden method ? Q3. What are different types of inner classes ? Ans. Simple Inner Class, Local Inner Class, Anonymous Inner Class , Static Nested Inner Class. Q4. Difference between TreeMap and HashMap ? Ans. They are different the way they are stored in memory. TreeMap stores the Keys in order whereas HashMap stores the key value pairs randomly. Q5. What is the difference between List, Set and Map ? Ans. List - Members are stored in sequence in memory and can be accessed through index. Set - There is no relevance of sequence and index. Sets doesn't contain duplicates whereas multiset can have duplicates. Map - Contains Key , Value pairs. Q6. Difference between Public...
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