转载：https://blog.csdn.net/qq_25827845/article/details/53868815

1.String源码中equals大致写法：

1 public boolean equals(Object anObject) { 2 if (this == anObject) { 3 return true; 4 } 5 if (anObject instanceof String) { 6 String anotherString = (String) anObject; 7 int n = value.length; 8 if (n == anotherString.value.length) { 9 char v1[] = value;10 char v2[] = anotherString.value;11 int i = 0;12 while (n-- != 0) {13 if (v1[i] != v2[i])14 return false;15 i++;16 }17 return true;18 }19 }20 return false;21 }

2. 模仿String equals源码

package cn.ywq.test; class MyString {        char[] value;    public MyString(char[] value) {        this.value=value;  //通过构造方法将字符传入    }            public int equalsString(Object obj) {        if(this==obj){            return 0;        }                //若该对象是MyString类型的        if(obj instanceof MyString){            MyString string =(MyString) obj;            int n=this.value.length;            if (n>string.value.length) {  //先判断长度的关系                return 1;            }else if(n
     
       v2[i]){                            return 1;                        }else if(v1[i] < v2[i]){                            return -1;                        }                                                        i++;                    }                    return 0;  //若while循环正常结束，则说明相等，返回0             }        }        return -100;  //若传入的不是MyString类型的对象            } }package cn.ywq.test; public class Test {     public static void main(String[] args) {                char[] value={'a','b','c','d'};//        char[] value2={'a','b','c','d','e'};//        char[] value3={'c','b','c','d'};        char[] value4={'a','b','c',};                MyString myString = new MyString(value);        MyString s=new MyString(value4);        int i = myString.equalsString(s);         System.out.println(i);    } }