MD5加密Util

目录

• (1)需要导入的包
• (2)MD5Util类
• (3)使用举例

(1)需要导入的包

    <dependency>
        <groupId>org.apache.commons</groupId>
        <artifactId>commons-lang3</artifactId>
        <version>3.3.2</version>
    </dependency>
    <dependency>
        <groupId>commons-codec</groupId>
        <artifactId>commons-codec</artifactId>
        <version>1.10</version>
    </dependency>

(2)MD5Util类

import org.apache.commons.codec.digest.DigestUtils;
import org.apache.commons.lang3.StringUtils;

import java.io.UnsupportedEncodingException;
import java.security.MessageDigest;
import java.util.Map;
import java.util.Set;
import java.util.TreeMap;


public class MD5Util {

	/**
	 * 字符串签名
	 * @param text    需要签名的字符串
	 * @param key     密钥
	 * @param charset 编码格式
	 * @return 签名结果
	 */
	public static String sign(String text, String key, String charset) {
		//拼接key
		text = text + key;
		return DigestUtils.md5Hex(getContentBytes(text, charset));
	}

	/**
	 * 根据参数map签名
	 * @param map 有序map
	 * @param key
	 * @param charset
	 * @return
	 */
	public static String sign(TreeMap<String, Object> map, String key, String charset){
		Set<String> keySet = map.keySet();
		StringBuilder sb = new StringBuilder();
		for (String mapKey : keySet){
			String value = (String)map.get(key);
			sb.append(key).append("=").append(value).append("&");
		}
		return sign(sb.toString(), key, charset);
	}


	/**
	 * 根据参数map签名
	 * @param map hashMap
	 * @param key
	 * @param charset
	 * @return
	 */
	public static String sign1(Map<String, Object> map, String key, String charset){
		Set<String> keySet = map.keySet();
		StringBuilder sb = new StringBuilder();
		for (String mapKey : keySet){
			String value = (String)map.get(key);
			sb.append(key).append("=").append(value).append("&");
		}
		return sign(sb.toString(), key, charset);
	}

	/**
	 * 根据参数map签名
	 * @param map hashMap
	 * @param key
	 * @param charset
	 * @return
	 */
	public static String sign(Map<String, String> map, String key, String charset){
		Set<String> keySet = map.keySet();
		StringBuilder sb = new StringBuilder();
		for (String mapKey : keySet){
			String value = (String)map.get(key);
			sb.append(key).append("=").append(value).append("&");
		}
		return sign(sb.toString(), key, charset);
	}

	/**
	 * 根据字符串获取byte[]
	 * @param content
	 * @param charset
	 * @return
	 */
	private static byte[] getContentBytes(String content, String charset){
		if (StringUtils.isEmpty(charset)) {
			return content.getBytes();
		}
		try {
			return content.getBytes(charset);
		} catch (UnsupportedEncodingException e) {
			throw new RuntimeException("转码过程中出现错误,指定的编码集不对,您目前指定的编码集是:" + charset);
		}
	}

	/**
	 * 签名，不用加密码
	 * @param origin
	 * @param charsetname
	 * @return
	 */
	public static String MD5Encode(String origin, String charsetname) {
		String resultString = null;
		try {
			resultString = new String(origin);
			MessageDigest md = MessageDigest.getInstance("MD5");
			if (charsetname == null || "".equals(charsetname))
				resultString = byteArrayToHexString(md.digest(resultString
						.getBytes()));
			else
				resultString = byteArrayToHexString(md.digest(resultString
						.getBytes(charsetname)));
		} catch (Exception exception) {
		}
		return resultString;
	}
	private static String byteArrayToHexString(byte b[]) {
		StringBuffer resultSb = new StringBuffer();
		for (int i = 0; i < b.length; i++)
			resultSb.append(byteToHexString(b[i]));

		return resultSb.toString();
	}

	private static String byteToHexString(byte b) {
		int n = b;
		if (n < 0)
			n += 256;
		int d1 = n / 16;
		int d2 = n % 16;
		return hexDigits[d1] + hexDigits[d2];
	}
	private static final String hexDigits[] = { "0", "1", "2", "3", "4", "5",
			"6", "7", "8", "9", "a", "b", "c", "d", "e", "f" };


}

(3)使用举例

//加密

//要加密的数据map<String, String>
Map<String, String> data = new TreeMap<String, String>();
String key="key123";//加密key  
String sign = MD5Util.sign(data, key, "utf-8");

//要加密的数据map<String, Object>
Map<String, Object> result = new TreeMap<String, Object>();
String key="key123";//加密key  
String sign = MD5Util.sign1(data, key, "utf-8");

//不用密码的加密，加密一个String
String sign=MD5Util.MD5Encode(mchkey, "utf-8");