1.String类 : String类的对象是已经创建便不能变动内容的字符串常量
- package javase.stu;
- import java.io.BufferedReader;
- import java.io.IOException;
- import java.io.InputStreamReader;
- public class StringTest {
- public static void main(String[] args) throws IOException {
- char c[] = {'i',' ','l','o','v','e',' ','u'};
- String s = "i love u";
- String s1 = new String(c,0,8);
- System.out.println(s);
- System.out.println(s1);
- String s2 = s.concat(s1);
- String s3 = s.replace('i', 'I');
- System.out.println(s);
- System.out.println(s2);
- System.out.println(s3);
- System.out.println(s.compareTo(s1));
- System.out.println(s.compareTo(s3));
- for(int i = 0; i < args.length; i++){
- System.out.println(args[i]);
- }
- InputStreamReader input = new InputStreamReader(System.in);
- BufferedReader read = new BufferedReader(input);
- System.out.println("input please !");
- String instr = read.readLine();
- System.out.println(instr);
- }
- }
2.StringBuffer类是一个在操作中可以变更其内容的字符串类,即一旦创建了StringBuffer类的对象,那么在操作中便可以更改和变动字符串的内容
- package javase.stu;
- public class StringBufferTest {
- public static void main(String[] args) {
- StringBuffer buff1 = new StringBuffer();
- StringBuffer buff2 = new StringBuffer(8);
- StringBuffer buff3 = new StringBuffer("i love u");
- // length()返回缓冲区中字符串的长度
- System.out.println(buff3.length());
- // capacity返回缓冲区的长度
- System.out.println(buff1.capacity());
- buff1.append("i love u");
- System.out.println(buff1);
- // 插入字符到下标处
- buff3.insert(7, "yo");
- System.out.println(buff3);
- }
- }