JavaDay-2

public class Main{
    public static void main(String[]args){
        String name = "MUHAHADAWANG";                       //相同堆内存
        System.out.println(name);                           //不同堆内存

        String englishName = new String("Guopeng");
        System.out.println(englishName);

        boolean same = name.equals(englishName);

        System.out.println(name+englishName);               //字符串内容不可改变，指向的内存改变了
        //字符串与字符数组的转化
        String str1 = "Helloo";
        char c[] = str1.toCharArray();
        String str2 = new String(c,0,3);
        //字符串取位置
        System.out.println(str1.charAt(2));
        //String 与 Byte 转换
        byte b[] = str1.getBytes();
        String str3 = new String(b);
        //获取String长度
        int len = str1.length();
        //查找，返回位置
        System.out.println(str1.indexOf("e"));
        //去掉左右空格
        System.out.println(str1.trim());
        //字符串截取
        System.out.println(str1.substring(2));
        //拆分，以String返回
        String s[] = str1.split("l");
        System.out.println(s[0]+"  "+s[2]);
        //大小写转换
        str1 = str1.toUpperCase();
        str2 = str2.toLowerCase();
        //判断以...开头/结尾
        boolean ok1 = str1.startsWith("s");
        boolean ok2 = str1.endsWith("ss");
        //不区别大小写进行比较
        boolean ok3 = str1.equalsIgnoreCase(str2);
        //替换 i -> x
        str1 = str1.replaceAll("i","x");
    }
}