第二部分面向对像基础第五章Strng类中方法的使用

package com.java.oop.day2;

import java.util.Calendar;
import java.util.Formatter;
import java.util.Locale;

public class StringClass {

	public static void main(String[] args) {
		// TODO Auto-generated method stub
		stringtoCharArray();//字符与字符串转换
		strinLenght();//字符串长度
		stringIndexOf();//字符串查找
		stringSubstring();//字符串截取
		strngSplit();//字符串拆分
		stringEquals();//字符串比较
	}

	//将此字符串转换为一个新的字符数组。
	public static void stringtoCharArray(){
		String str = new String("hello");
		char c[] = str.toCharArray();
		for(int i = 0 ; i < str.length();i++){
			System.out.print(c[i]+" ");
		}
		System.out.println();
		String str1 = new String(c);//将字符数组转换为一个新的字符串。
		System.out.println(str1);
		System.out.println(str.charAt(3));//取出字符串中的第四个字符。
	}
	//字符串长度
	public static void strinLenght(){
		String str = "OF";
		System.out.println("字符串长度"+str.length());
	}
	//查找字符串是否存在
	public static void stringIndexOf(){
		String str = "  string  ";
		System.out.println(str.indexOf("g"));
		System.out.println(str.indexOf("t",1));
		//去除字符串两边的空格
		System.out.println(str.trim());
		//System.out.println(str);
	}
	//字符串截取
	public static void stringSubstring(){
		String str = "hello";
		String str1 = str.substring(0, 3);
		System.out.println("字符串截取="+str1);
	}
	//拆分字符串
	public static void strngSplit(){
		String str = "he,ll,o";
		String s[] = str.split(",");
		for(int i = 0; i <s.length ;i++){
			System.out.println(s[i]);
		}
	}
	//字符串比较
	public static void stringEquals(){
		String str = "hello";
		String str1 = "hello";
		String str2 = "";
		if(str.equals(str1))System.out.println(true);
		if(str2.isEmpty())System.out.println(true);
		//格式化日期
		StringBuilder sb = new StringBuilder();
		Formatter formatter = new Formatter(sb, Locale.US);
		formatter.format("年-月-日:: %1$tY-%1$te-%1$tm", Calendar.getInstance());
		System.out.println();
		System.out.println(formatter);
		System.out.println();
		System.out.format("年-月-日: %1$tY-%1$te-%1$tm", Calendar.getInstance());
		System.out.println();
		Formatter formatter1 = new Formatter(sb, Locale.US);
		formatter1.format("时间: %1$tH:%1$tM", Calendar.getInstance());
		System.out.println();
		System.out.println(formatter1);

	}
}