Java中== equals hashcode浅析

class Product {
	private int id;
	private String name;
	
	public Product(int id, String name) {
		this.id = id;
		this.name = name;
	}
	
	@Override 
	public boolean equals(Object obj) {
		if (obj == null) {
			return false;
		}
		if (!(obj instanceof Product)) {
			return false;
		}
		Product other = (Product)obj;
		if (other.id != this.id) {
			return false;
		}
		return true;
	}
}


public class EqualsTest {
	public static void main(String[] args) {
		Product a = new Product(1, "zcl");
		Product b = new Product(1, "chunlei");

		System.out.println("equals: " + a.equals(b)); 
		System.out.println("a.hashCode:" + a.hashCode()); 
		System.out.println("b.hashCode:" + b.hashCode());
	}
}
/** (output)

D:\My Documents\javacode>javac EqualsTest.java

D:\My Documents\javacode>java EqualsTest
equals: true
a.hashCode:12677476
b.hashCode:33263331

*/