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Renewal·서른의 생활코딩

Java Lecture Notes - 2012.02.20 (Part 2)

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StringBuffer

     public final class StringBuffer  -> final:inheritanceX
     extends Object
     implements Serializable, CharSequence serialization



usage type)
  - StringBuffer() : memory saving , stringfaster than.
                             implicitly 16characters store possible object creation
                             (when initial value not specified)
 

  - StringBuffer(int size)   : size size object creation

  - StringBuffer(String str) : str specified as string
                                          additionally 16characters more store possible object creation



 

 


java.lang package : all Java program auto included as package


   Number:abstract class -> objectdefinitionnewoperation not usable ,referencevariable useonly possible

           public abstract class Number  ->abstract abstract->objectdefinitionX

           extends Object

           implements Serializable

 

           objectdefinition forX

           sub class inheritancefor making 

            ( AtomicInteger, AtomicLong, BigDecimal, BigInteger, Byte, 

               Double, Float, Integer, Long, Short)


    Math : stativmemberfunction
 

    Object class 
 

    Equals() : function basichandling: addressvalue comparison + re-definition needed.
 

    clone()  : protected Object clone()   //externalfrom accessX
                    throws CloneNotSupportedException 
                             // Exception try catch block only through call possible. 

                             // (exception handling forcreated function!)

 
   wrapper(Wrapper) class : 8to's basic data type object use possible class provide.

                  // : Boolean, Character, Byte, Short, Integer, Long, Float, Double

                  // Number class inheritance



   Integer CLASS

              public final class Integer

              extends Number

              implements Comparable<Integer>


   exception handling :try,catch block creates.(more complete program for)

 

This English version was translated by Claude.

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Pleasant Charles — UI/UX researcher at AIT. Keeping notes on design, planning, and slow days here since 2010.

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