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greeting=greeting.substring(0,3)+"p!";
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String str="Hello";
String str1="World";
System.out.println(str+str1=="HelloWorld"); //false
System.out.println(str.substring(0,3)=="Hel"); //false
System.out.println(str=="Hello"); //true
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package com.lihp.exl;
/**
Ä¿µÄ£ºÌṩÓÉÊý¾Ý¶ÔÏ󼯺ÏÀࣨVector£©Éú³ÉExcel¹¤×÷±íµÄ¹¦ÄÜ
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*/
import java.io.*;
import java.util.*;
import java.lang.reflect.Method;
import org.apache.poi.hssf.usermodel.HSSFSheet;
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