Question

我必须创建一个equals方法，如果Politicians＆＃39;标题是一样的。我如何比较字符串？

到目前为止，这是我尝试编写的方式：

import socket
import struct
import binascii
rawSocket = socket.socket(socket.AF_PACKET, socket.SOCK_RAW, socket.htons(0x0003))
while True:
    packet = rawSocket.recvfrom(2048)
    ethernet_header = packet[0][0:14]
    ethernet_detailed = struct.unpack(“!6s6s2s”, ethernet_header)
    arp_header = packet[0][14:42]
    arp_detailed = struct.unpack(“2s2s1s1s2s6s4s6s4s”, arp_header)
    # skip non-ARP packets
    ethertype = ethernet_detailed[2]
    if ethertype != ‘\x08\x06’:
        continue
    source_mac = binascii.hexlify(arp_detailed[5])
    dest_ip = socket.inet_ntoa(arp_detailed[8])
    if source_mac == ‘74c24671971c’:
        print “Tide button pressed!, IP = “ + dest_ip

然而，它总是返回false。即使我测试：

public class Politician implements Priority{
private String name, title;
private int a;
public Politician(String n, String t, int p){
    name=n;
    title=t;
    a=p;
}
public boolean equals(Politician a){
    if(title.equals(a.title))
        return true;
    return false;
}

之前我写过equals（）并且我不知道为什么它不再工作了

Answer 1

public boolean equals（Politician a）不会覆盖类java.lang.Object中的equals方法。

声明为公共布尔值等于（对象a）以覆盖该方法。

public boolean equals(Object a) {
        Politician p = (Politician) a;
        return title.equals(p.title);
    }

顺便说一句，在政治家课程中使用p.title是完全合法的，即使在政治家课程中标题是私人的。查看这篇文章：Access private field of another object in same class

Answer 2

试试这个：

public class Politician extends Priority{

    public String name, title;
    public int a;

    public Politician(String n, String t, int p) {
        name = n;
        title = t;
        a = p;
    }

    public boolean equals(Object o) {
        Politician a = (Politician) o;
        //System.out.println(a.title +" -  "+title);
        if (title.equals(a.title)) {

            return true;
        }
        return false;
    }

    public static void main(String[] args) {
        Priority t4 = new Politician("Arnie", "Governor", 4);
        Politician t5 = new Politician("Bill", "Governor", 10);
        System.out.println(t5.equals(t4));
        System.out.println(t4.equals(t5));
    }
}

使用java比较字符串

2 个答案: