JAVAÖØÐ´equals·½·¨
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public class Coordinate {
public int headX, headY;
Coordinate(int headX, int headY) {
this.headX = headX;
this.headY = headY;
}
public boolean equals(Coordinate c) {
if(this.headX == c.headX && this.headY == c.headY) {
return true;
} else {
return false;
}
}
˵Ã÷£ºCoordinate ÊÇÒ»¸ö×ø±êÀà£¬ÖØÐ´equals·½·¨µÄÔÒòÊÇÒª±È½ÏÉßÉíÊÇ·ñµ½´ïÁ˼ǼÏÂÀ´µÄÉßÍ·µÄתÍäµã£¬ÓÚÊÇ×Ô¼ºÖØÐ´ÁËequals·½·¨£¬µ«ÊÇ·¢ÏÖûÓÐЧ¹û£¬¼´Ê¹x£¬yµÄÖµÒ»Ñù£¬·µ»ØµÄÒ²ÊÇfalse¡£
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public class TestEquals {
public static void main(String[] args) {
Dog d1 = new Dog(1);
Dog d2 = new Dog(1);
System.out.println(d1 == d2);
System.out.println(d1.equals(d2));
}
}
class Dog {
int weight;
Dog(int weight) {
this.weight = weight;
}
public boolean equals(Dog d) {
if(this.weight == d.weight) {
return true;
} else {
return false;
}
}
}
µ±È»½á¹ûÊÇÒ»ÑùµÄ£¬ÎªÁ˽øÒ»²½ÑéÖ¤£¬ÓÚÊǾͽøÒ»²½ÖØÐ´ÁËhashCode()·½·¨£º
public int hashCode() {
return 0;
}
ÒòΪÓÐʱºòÓÅÏȱȽϵÄÊÇhashCodeÂë¡£µ«Êǽá¹û»¹ÊDz»ÐС£ÎÒÖ»ºÃÕÒ»ØÔÀ´¿´¹ýµÄÂíÊ¿±øÀÏʦµÄÊÓÆµ½Ì³Ì£¬²Å·¢ÏÖ×Ô¼º¶ÔÕâ¸öÖØÐ´ºÜ²»ÊìϤ£¬ÕýÈ·µÄд·¨Ó¦¸ÃÊÇ£º
public class Coordinate {
public int headX, headY;
Coordinate(int headX, int headY) {
this.headX = headX;
this.headY = headY;
}
public int hashCode() {
return 0;
}
public boolean equals(Object obj) {
if(obj == null) {
return false;
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