源程序: import javax.swing.JOptionPane; public class Java_1 public static void main(String args[]) String s1,s2,s3,s4,output; s1=new String("hello"); s2=new String("good bye"); s3=new String("Happy Birthday"); s4=new String("happy birthday"); output="s1="+s1+"ins2="+s2+"ins3="+s3+"ins4="+s4+"\n\n" //测试字符串相等 if(s1.equals("hello"))output=output+" (1) "; else output=output+"s1 does not equal\"hello\"\n": //用==测试相等 if(s1=="hello")output+="s1 equals\"hello\"in": else output+="s1 does not equal\"hello\"\n": //忽略字符格式测试相等 if(s3.equalsIgnoreCase(s4))output+="s3 equals s4\n": else output+="s3 does not equal s4\n": //内容比较 output+="\ns1.compareTo(s2)is"+s1.compareTo(s2)+"\ns2.compareTo(s1)is" +s2.compareTo(s1)+"\ns1.compareTo(s1)is"+s1.compareTo(s1) +"\ns3.compareTo(s4)is"+s3.compareTo(s4)+"\ns4.compareTo(s3)is" +s4.compareTo(s3)+”\n\n“; //80试包含字符格式的域匹配 if(s3.regionMatehes(0,s4,0,5))output+="First 5 characters of s3 and s4 match\n": else output+="First 5 characters of s3 and s4 do not match\n": //忽略字符格式的域匹配 if(s3.regionMatches(true,0,s4,0,5))output+="First 5 characters of s3 and s4 match": else output+="First 5 characters of s3 and s4 do not match": JOptionPane. (2) (null,output, "字符串构造方法示例",JOptionPane.INFORMATION_MESSAGE): System.exit(0);