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public static void main(String[] args)
{
StringBuffer str1 = new StringBuffer("hello");
test(str1);
System.out.println("main : " + str1);
}
public static void test(StringBuffer str)
{
StringBuffer tempStr = new StringBuffer();
System.out.println("first : " + str);
str = str.append(" world");
System.out.println("second: " + str);
str = tempStr;
System.out.println("third : " + str);
}
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first : hello
second: hello world
third :
main : hello world
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test(str1);
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str = str.append(" world");
ÓÉÓÚstrͬÑùÒ²ÊÇÖ¸Ïò"hello"¶ÔÏó£¬ËùÒԸòÙ×÷»á¸Ä±ä¶ÔÏó±¾Éí"hello"±ä³É"hello world";
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str = tempStr;
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