微信小程序后台获取用户手机号工具类

需求:小程序获取用户手机号（需要用户授权）、

参数：encryptedData  加密数据；session_key；iv  加密算法的初始向量

返回值：result   type: String

用到的jar：请添加到pom.xml文件中

<!-- -- https://mvnrepository.com/artifact/org.bouncycastle/bcprov-jdk15on --> -->
<dependency>
    <groupId>Id>org.bouncycastle<tle</groupId>
    <artifactId>bcprov-jdk15on</artifactId>
    <version>1.54</version>
</dependency>

<dependency>
    <groupId>org.apache.shiro</groupId>
    <artifactId>shiro-core</artifactId>
    <version>1.2.3</version>
</dependency>

工具类：

package com.learn.utils;
import java.security.AlgorithmParameters;
import java.security.Security;
import java.util.Arrays;
import javax.crypto.Cipher;
import javax.crypto.spec.IvParameterSpec;
import javax.crypto.spec.SecretKeySpec;
public class WXUtil {
	/**
	 * @author ahk
	 * @param encryptedData  加密数据
	 * @param key  session_key
	 * @param iv  加密算法的初始向量
	 * @return  result   type:	String
	 */
	public static String decrypt(String encryptedData, String key, String iv) {
			 // 被加密的数据
            byte[] dataByte = org.apache.shiro.codec.Base64.decode(encryptedData);
            // 加密秘钥
            byte[] keyByte = org.apache.shiro.codec.Base64.decode(key);
            // 偏移量
            byte[] ivByte = org.apache.shiro.codec.Base64.decode(iv);
            try {
                // 如果密钥不足16位，那么就补足. 
                int base = 16;
                if (keyByte.length % base != 0) {
                    int groups = keyByte.length / base + (keyByte.length % base != 0 ? 1 : 0);
                    byte[] temp = new byte[groups * base];
                    Arrays.fill(temp, (byte) 0);
                    System.arraycopy(keyByte, 0, temp, 0, keyByte.length);
                    keyByte = temp;
                }
                // 初始化
                Security.addProvider(new  org.bouncycastle.jce.provider.BouncyCastleProvider());
                Cipher cipher = Cipher.getInstance("AES/CBC/PKCS5Padding");
                SecretKeySpec spec = new SecretKeySpec(keyByte, "AES");
                AlgorithmParameters parameters = AlgorithmParameters.getInstance("AES");
                parameters.init(new IvParameterSpec(ivByte));
                cipher.init(Cipher.DECRYPT_MODE, spec, parameters);// 初始化
                byte[] resultByte = cipher.doFinal(dataByte);
                if (null != resultByte && resultByte.length > 0) {
                    String result = new String(resultByte, "UTF-8");
                   /* return JSONObject.parseObject(result);*/
                    return result;
                }
            } catch (Exception e) {
                e.printStackTrace();
            }
		
		return null;
	}
	
	public static void main(String[] args) {
		String result = decrypt("填写你的加密数据", "填写你的session_key", "填写返回的vi");
		System.out.println(result);
	}

}

这样返回值为json字符串的工具类就已经成功了！