Java面向对象程序设计CORE-06.ppt

示例：使用String的方法publicclassTestString{ publicstaticvoidmain(String[]args){ Stringtext=HelloWorld; intlen=text.length(); charch=text.charAt(6); intpos=text.indexOf(s); Stringsub=text.substring(0,5); Stringupper=text.toUpperCase(); Stringlower=text.toLowerCase(); System.out.println(原字符串是：+text); System.out.println(字符串长度为：+len); System.out.println(索引为6的字符是：+ch); System.out.println(字符s的索引位置是：+pos); System.out.println(索引从0到5的子串为：+sub); System.out.println(大写字符串为：+upper); System.out.println(小写字符串为：+lower); System.out.println(原字符串是：+text); }}示例演示：publicclassStringConstructors{publicstaticvoidmain(String[]args){Stringstr1=newString();Stringstr2=newString(Hello);char[]charArr={w,i,s,h};Stringstr3=newString(charArr);System.out.println(str1:+str1);System.out.println(str2:+str2);System.out.println(str3:+str3);}}StringBuffer类的方法示例publicclassTestStringBuffer{publicstaticvoidmain(String[]args){StringBufferbuffer=newStringBuffer(world);System.out.println(buffer.toString());System.out.println(长度为：+buffer.length());System.out.println(容量为：+buffer.capacity());buffer.setCharAt(0,W);buffer.append(!);buffer.append(Hereweare!);buffer.insert(0,Hello);System.out.println(buffer.toString());System.out.println(长度为：+buffer.length());System.out.println(容量为：+buffer.capacity());}}StringBuffer类的方法示例publicclassTestStringBuffer{publicstaticvoidmain(String[]args){StringBufferbuffer=newStringBuffer(“world);System.out.println(buffer.toString());System.out.println(长度为：+buffer.length());System.out.println(容量为：+buffer.capacity());buffer.setCharAt(0,W);buffer.append(!);buffer.