字符串面试题：以下程序的输出结果是

import java.util.*;
/**
 * Description:
 * <br/>网站: <a href="http://www.crazyit.org">疯狂Java联盟</a>
 * <br/>Copyright (C), 2001-2016, Yeeku.H.Lee
 * <br/>This program is protected by copyright laws.
 * <br/>Program Name:
 * <br/>Date:
 * @author Yeeku.H.Lee [e-mail]
 * @version 1.0
 */
public class DiamondTest
{
public static void main(String[] args)
{
String s = "hello";
String t ="hello";
String str = "hello";
char c[] ={'h','e','l','l','o'};

char ch[] =str.toCharArray();
if(ch==c)
System.out.println("true");
else
System.out.println("false");
if(ch.equals(c))
System.out.println("true");
else
System.out.println("false");

String s2 = new String(c);
if(s2==(s))
System.out.println("true");
else
System.out.println("false");
if(s2.equals(s))
System.out.println("true");
else
System.out.println("false");


}

}

output:

false
false
false
true

------------------------------------------------------------------StringBuffer面试题------------------------------------------------------------------

public class DiamondTest
{
public static void main(String[] args)
{
StringBuffer a = new StringBuffer("A");
StringBuffer b = new StringBuffer("B");
operate(a,b);
System.out.println(a+","+b);
}
static void operate(StringBuffer x,StringBuffer y)
{
x.append(y);
y=x;
}
}

输出结果:AB,B