java-参考支付宝加密方式

package com.util;

import java.security.MessageDigest;
import java.util.Map;
import java.util.TreeMap;

import com.config.ConstantConfiguer;
import com.exp.RunException;

public class EncryptUtils {
	public static String getSign(Map<String, String> map) {
		String sign = "";
		if (Helper.isNull(map)) {
			throw new RunException("encrypt data is empty");
		}
		TreeMap<String, String> treeMap = new TreeMap<String, String>();
		treeMap.putAll(map);
		treeMap.put("privateKey", "Key" );
		StringBuffer buffer = new StringBuffer();
		for (Map.Entry<String, String> entry : treeMap.entrySet()) {
			buffer.append(entry.getKey()).append("=").append(entry.getValue())
					.append("&");
		}
		int length = buffer.length();
		buffer.delete(length - 1, length);
		sign = SHA1.sha(buffer.toString()).toLowerCase();
		return sign;
	}

	/**
	 * 加密字符串
	 */
	public static String getSign(String txt) {
		return getSign(txt, "HelloWord" );
	}

	public static String getSign(String txt, String key) {
		if (Helper.isNull(txt)) {
			throw new RunException("encrypt data is empty");
		}
		String sign = null;
		txt = txt + "-" + key;
		sign = SHA1.sha(txt).toLowerCase();
		return sign;
	}
}

class SHA1 {
	public static void main(String[] args) {
		System.out.println(sha(""));
	}

	public static String md5(String inputText) {
		return encrypt(inputText, "md5");
	}

	public static String sha(String inputText) {
		return encrypt(inputText, "sha-1");
	}

	private static String encrypt(String inputText, String algorithmName) {
		inputText = Helper.checkNull(inputText);
		if (algorithmName == null || "".equals(algorithmName.trim())) {
			algorithmName = "md5";
		}
		String encryptText = null;
		try {
			MessageDigest m = MessageDigest.getInstance(algorithmName);
			m.update(inputText.getBytes("UTF8"));
			byte s[] = m.digest();
			return hex(s);
		} catch (Exception e) {
			e.printStackTrace();
		}
		return encryptText;
	}

	private static String hex(byte[] arr) {
		StringBuffer sb = new StringBuffer();
		for (int i = 0; i < arr.length; ++i) {
			sb.append(Integer.toHexString((arr[i] & 0xFF) | 0x100).substring(1,
					3));
		}
		return sb.toString();
	}
}

java-参考支付宝加密方式