StringBuffer的append源码解析（模拟源码）

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package array;import java.lang.*; /** * @author wbl * 2017-1-6 * @describe 分析StringBuffer如何append */public class ArrayTest {   public static void main(String[] args) {  StringBuilder sb2 = new StringBuilder("abc");  //这一步，源码AbstractStringBuilder类     value=char[8];count=3;  sb2.append("d");  //这一步， str.getChars(0, 1, value, 3);  str.getChars(0, len, value, count);  //得出 char = abcd  char chr1[] = new char[8];  chr1[0] = 'a';  chr1[1] = 'b';  chr1[2] = 'c';      //getChars(int srcBegin, int srcEnd, char[] dst, int dstBegin)      String str = "d000";      str.getChars(0, 1, chr1, 3);      System.out.print("char = ");      System.out.print(chr1[0]);      System.out.print(chr1[1]);      System.out.print(chr1[2]);      System.out.println(chr1[3]);            // arraycopy(Object src, int srcPos, Object dest, int destPos, int length)      //String类getchars方法    arraycopy(value, srcBegin, dst, dstBegin, srcEnd - srcBegin)      char chr2[] = { 'd'};          System.arraycopy(chr2, 0, chr1, 3, 1);      System.out.print("array2 = ");      System.out.print(chr1[0] + " ");      System.out.print(chr1[1] + " ");      System.out.print(chr1[2] + " ");      System.out.print(chr1[3] + " ");   }}

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