Java 微信公众号开发--- 接入微信

开发微信公众号在没有正式的公众平台账号时，我们可以使用测试平台账号———

测试平台申请地址：https://mp.weixin.qq.com/debug/cgi-bin/sandbox?t=sandbox/login

开发者文档：https://mp.weixin.qq.com/wiki?t=resource/res_main&id=mp1445241432

进入之后我们会看见此时appID、appsecret都有了，url是我们成为开发者与微信进行的一次握手配置（url其实就是我们项目中你controller的访问地址，token是我们自己填写的，可在后台进行判断的），这里的url可以用ngrok来做映射，这样开发起来比较方便，ngrok配置（点击查看）ngrok下载地址（点击下载）

我们可以在开发者文档中看见

这里查看详细配置；期间我们要说道微信会给我们的url通过get方式传递4个参数

下面我们来看一下controller怎么编写

package com.website.wechat.controller;

import java.io.IOException;
import java.security.MessageDigest;
import java.util.ArrayList;
import java.util.Collections;
import java.util.List;

import javax.servlet.http.HttpServletRequest;
import javax.servlet.http.HttpServletResponse;

import org.springframework.stereotype.Controller;
import org.springframework.web.bind.annotation.RequestMapping;
import org.springframework.web.bind.annotation.RequestMethod;
import org.springframework.web.bind.annotation.ResponseBody;

@Controller
@RequestMapping(value="weixin")
public class WeiXinController {

    private static final char[] HEX_DIGITS = { '0', '1', '2', '3', '4', '5',
        '6', '7', '8', '9', 'a', 'b', 'c', 'd', 'e', 'f' };

    @RequestMapping(value="getWeiXinMethod",method=RequestMethod.GET)
    @ResponseBody
    public void getWeiXinMethod(HttpServletRequest request, HttpServletResponse response) throws IOException{
        boolean validate = validate(request);
        if (validate) {
            response.getWriter().write(request.getParameter("echostr"));
            response.getWriter().close();
        }

    }

    private boolean validate(HttpServletRequest req) throws IOException {
        String signature = req.getParameter("signature");//微信加密签名
        String timestamp = req.getParameter("timestamp");//时间戳
        String nonce = req.getParameter("nonce");//随机数
        List<String> list = new ArrayList<String>();
        list.add("chenchen");
        list.add(timestamp);
        list.add(nonce);
        Collections.sort(list);//字典排序
        String s = "";
        for (int i = 0; i < list.size(); i++) {
            s += (String) list.get(i);
        }
        if (encode("SHA1", s).equalsIgnoreCase(signature)) {
            return true;
        } else {
            return false;
        }
    }

    public static String encode(String algorithm, String str) {
        if (str == null) {
            return null;
        }
        try {
            //Java自带的加密类
            MessageDigest messageDigest = MessageDigest.getInstance(algorithm);
            //转为byte
            messageDigest.update(str.getBytes());
            return getFormattedText(messageDigest.digest());
        } catch (Exception e) {
            throw new RuntimeException(e);
        }
    }

    private static String getFormattedText(byte[] bytes) {
        int len = bytes.length;
        StringBuilder buf = new StringBuilder(len * 2);
        // 把密文转换成十六进制的字符串形式
        for (int j = 0; j < len; j++) {
            buf.append(HEX_DIGITS[(bytes[j] >> 4) & 0x0f]);
            buf.append(HEX_DIGITS[bytes[j] & 0x0f]);
        }
        return buf.toString();
    }
}

package com.website.wechat.controller;
import java.io.IOException;

import java.security.MessageDigest;

import java.util.ArrayList;

import java.util.Collections;

import java.util.List;
import javax.servlet.http.HttpServletRequest;

import javax.servlet.http.HttpServletResponse;
import org.springframework.stereotype.Controller;

import org.springframework.web.bind.annotation.RequestMapping;

import org.springframework.web.bind.annotation.RequestMethod;

import org.springframework.web.bind.annotation.ResponseBody;
@Controller

@RequestMapping(value="weixin")

public class WeiXinController {
private static final char[] HEX_DIGITS = { '0', '1', '2', '3', '4', '5',
	'6', '7', '8', '9', 'a', 'b', 'c', 'd', 'e', 'f' };

@RequestMapping(value="getWeiXinMethod",method=RequestMethod.GET)
@ResponseBody
public void getWeiXinMethod(HttpServletRequest request, HttpServletResponse response) throws IOException{
	boolean validate = validate(request);
	if (validate) {
		response.getWriter().write(request.getParameter("echostr"));
		response.getWriter().close();
	}
	
}

private boolean validate(HttpServletRequest req) throws IOException {
	String signature = req.getParameter("signature");//微信加密签名
	String timestamp = req.getParameter("timestamp");//时间戳
	String nonce = req.getParameter("nonce");//随机数
	List<String> list = new ArrayList<String>();
	list.add("chenchen");
	list.add(timestamp);
	list.add(nonce);
	Collections.sort(list);//字典排序
	String s = "";
	for (int i = 0; i < list.size(); i++) {
		s += (String) list.get(i);
	}
	if (encode("SHA1", s).equalsIgnoreCase(signature)) {
		return true;
	} else {
		return false;
	}
}

public static String encode(String algorithm, String str) {
	if (str == null) {
		return null;
	}
	try {
		//Java自带的加密类
		MessageDigest messageDigest = MessageDigest.getInstance(algorithm);
		//转为byte
		messageDigest.update(str.getBytes());
		return getFormattedText(messageDigest.digest());
	} catch (Exception e) {
		throw new RuntimeException(e);
	}
}

private static String getFormattedText(byte[] bytes) {
	int len = bytes.length;
	StringBuilder buf = new StringBuilder(len * 2);
	// 把密文转换成十六进制的字符串形式
	for (int j = 0; j < len; j++) {
		buf.append(HEX_DIGITS[(bytes[j] >> 4) & 0x0f]);
		buf.append(HEX_DIGITS[bytes[j] & 0x0f]);
	}
	return buf.toString();
}

}

此时验证和调用已经没问题，成功介入微信，成为一名开发者