支付系统中的常用工具

• StringUtils.java

　　处理常用字符串：判断是否为空 isEmpty(String value);

　　按字典排序并拼接参数：createLinkString(Map params);

  import java.util.ArrayList;
  import java.util.Collections;
  import java.util.List;
  import java.util.Map;

  public class StringUtils {
	  /**
	   * 判断字符数组是否为空
	   */
	  public static boolean areNotEmpty(String... values) {
		  boolean result = true;
		  if (values == null || values.length == 0) {
			  result = false;
		  } else {
			  for (String value : values) {
				  result &= !isEmpty(value);
			  }
		  }
		  return result;
	  }

	  /**
	   * 把数组所有元素排序，并按照"name1=value1&name2=value2..."字符拼接成字符串
	   * 
	   * @param params
	   *            需要排序并参与字符拼接的参数组
	   * @return 拼接后字符串
	   */
	  public static String createLinkString(Map<String, String> params) {

		  List<String> keys = new ArrayList<String>(params.keySet());
		  Collections.sort(keys);

		  String prestr = "";

		  for (int i = 0; i < keys.size(); i++) {
			  String key = keys.get(i);
			  String value = params.get(key);

			  if (i == keys.size() - 1) {
				  prestr = prestr + key + "=" + value;
			  } else {
				  prestr = prestr + key + "=" + value + "&";
			  }
		  }

		  return prestr;
	  }

	  /**
	   * 判断字符串是否为空
	   * <ul>
	   * <li>isEmpty(null) = true</li>
	   * <li>isEmpty("") = true</li>
	   * <li>isEmpty("   ") = true</li>
	   * <li>isEmpty("abc") = false</li>
	   * </ul>
	   * 
	   * @param value
	   *            目标字符串
	   * @return true/false
	   */
	  public static boolean isEmpty(String value) {
		  int strLen;
		  if (value == null || (strLen = value.length()) == 0) {
			  return true;
		  }
		  for (int i = 0; i < strLen; i++) {
			  if ((Character.isWhitespace(value.charAt(i)) == false)) {
				  return false;
			  }
		  }
		  return true;
	  }
  }

• 支付系统中的签名和验签 SignUtils.java
  import java.io.InputStream;
  import java.security.KeyStore;
  import java.security.PrivateKey;
  import java.security.PublicKey;
  import java.security.cert.Certificate;
  import java.security.cert.CertificateFactory;
  import java.util.ArrayList;
  import java.util.Collections;
  import java.util.Enumeration;
  import java.util.HashMap;
  import java.util.List;
  import java.util.Map;
  import org.apache.commons.codec.binary.Base64;

  /**

  */
  public class SignUtils {

  /**  */
  // 缓存公钥和私钥
  public static Map<String, Object> certMap = new java.util.concurrent.ConcurrentHashMap<String, Object>();
  
  /**
   * 
   *
   * @param sArray 
   * @return 
   */
  public static Map<String, String> paraFilter(Map<String, String> sArray) {
  
  	Map<String, String> result = new HashMap<String, String>();
  
  	if (sArray == null || sArray.size() <= 0) {
  		return result;
  	}
  
  	for (String key : sArray.keySet()) {
  		String value = sArray.get(key);
  		if (value == null || StringUtils.isEmpty(value)
  				|| key.equalsIgnoreCase("sign")) {
  			continue;
  		}
  		result.put(key, value);
  	}
  
  	return result;
  }
  
  
  /**
   * 
   *
   * @param sortedParams 
   * @return 
   */
  public static String getSignContent(Map<String, String> sortedParams) {
  	StringBuffer content = new StringBuffer();
  	List<String> keys = new ArrayList<String>(sortedParams.keySet());
  	Collections.sort(keys);
  	int index = 0;
  	for (int i = 0; i < keys.size(); i++) {
  		String key = keys.get(i);
  		String value = sortedParams.get(key);
  		if (StringUtils.areNotEmpty(key, value)) {
  			content.append((index == 0 ? "" : "&") + key + "=" + value);
  			index++;
  		}
  	}
  	return content.toString();
  }
  
  
  /**
   * 
   * 签名
   * @param params 业务参数 
   * @param charset 编码
   * @param pfxCertFileInputStream 证书输入流 
   * @param rsaPassword  私钥pkcs12证书密码
   * @param algorithmName rsa算法名
   * @return 
   * @throws Exception 
   */
  public static String rsaSign(Map<String, String> params, String charset,
  		InputStream pfxCertFileInputStream,String rsaPassword, String algorithmName) throws Exception {
  	String signContent = getSignContent(params);
  
  	return rsaSign(signContent, charset, pfxCertFileInputStream,rsaPassword, algorithmName);
  }
  
  /**
   * 
   *
   * @param content 
   * @param charset 
   * @param pfxCertFileInputStream 
   * @param rsaPassword 
   * @param algorithmName 
   * @return 
   * @throws Exception 
   */
  public static String rsaSign(String content, String charset,
  		InputStream pfxCertFileInputStream,String rsaPassword, String algorithmName) throws Exception {
  	try {
  		PrivateKey priKey = getPrivateKeyFromPKCS12(
  				rsaPassword,
  				pfxCertFileInputStream);
  
  		java.security.Signature signature = java.security.Signature
  				.getInstance(algorithmName);
  
  		signature.initSign(priKey);
  
  		if (StringUtils.isEmpty(charset)) {
  			signature.update(content.getBytes());
  		} else {
  			signature.update(content.getBytes(charset));
  		}
  
  		byte[] signed = signature.sign();
  
  		String sign = new String(Base64.encodeBase64(signed), charset);
  
  
  		return sign;
  	} catch (Exception e) {
  		throw new Exception("RSAcontent = " + content + "; charset = "
  				+ charset, e);
  	}
  }
  
  /**
   * 
   *
   * @param publicCertFileInputStream 
   * @param params 
   * @param sign 
   * @param charset 
   * @param algorithmName 
   * @return 
   * @throws Exception 
   */
  public static boolean rsaCheckContent(
  		InputStream publicCertFileInputStream, Map<String, String> params,
  		String sign, String charset,String algorithmName) throws Exception {
  	String content = StringUtils.createLinkString(SignUtils
  			.paraFilter(params));
  
  	return rsaCheckContent(publicCertFileInputStream, content, sign,
  			charset, algorithmName);
  }
  
  
  /**
   * 
   *
   * @param publicCertFileInputStream 
   * @param content 
   * @param sign 
   * @param charset 
   * @param algorithmName 
   * @return 
   * @throws Exception 
   */
  public static boolean rsaCheckContent(
  		InputStream publicCertFileInputStream, String content, String sign,
  		String charset, String algorithmName) throws Exception {
  	boolean bFlag = false;
  	try {
  		java.security.Signature signetcheck = java.security.Signature
  				.getInstance(algorithmName);
  		signetcheck
  				.initVerify(getPublicKeyFromCert(publicCertFileInputStream));
  		signetcheck.update(content.getBytes(charset));
  		if (signetcheck.verify(Base64.decodeBase64(sign.getBytes(charset)))) {
  			bFlag = true;
  			System.out.println("签名成功！");
  		}else{
  			System.out.println("签名失败！");
  		}
  	} catch (Exception e) {
  		throw new Exception("验证签名异常");
  	}
  
  	return bFlag;
  }
  
  /**
   * 读取公钥，x509格式.
   *
   * @param ins 
   * @return 
   * @throws Exception 
   */
  public static PublicKey getPublicKeyFromCert(InputStream ins)
  		throws Exception {
  	PublicKey pubKey = (PublicKey) certMap.get("PublicKey");
  	if (pubKey != null) {
  		return pubKey;
  	}
  
  	try {
  		CertificateFactory cf = CertificateFactory.getInstance("X.509");
  		Certificate cac = cf.generateCertificate(ins);
  		pubKey = cac.getPublicKey();
  		certMap.put("PublicKey", pubKey);
  	} catch (Exception e) {
  		if (ins != null)
  			ins.close();
  		throw e;
  	} finally {
  		if (ins != null) {
  			ins.close();
  		}
  	}
  
  	return pubKey;
  }
  
  /**
   * 读取PKCS12格式的key（私钥）pfx格式.
   *
   * @param rsaPassword 
   * @param ins 
   * @return 
   * @throws Exception 
   */
  public static PrivateKey getPrivateKeyFromPKCS12(String rsaPassword,
  		InputStream ins) throws Exception {
  	PrivateKey priKey = (PrivateKey) certMap.get("PrivateKey");
  	if (priKey != null) {
  		return priKey;
  	}
  
  	KeyStore keystoreCA = KeyStore.getInstance("PKCS12");
  	try {
  		// 读取CA根证书
  		keystoreCA.load(ins, rsaPassword.toCharArray());
  
  		Enumeration<?> aliases = keystoreCA.aliases();
  		String keyAlias = null;
  		if (aliases != null) {
  			while (aliases.hasMoreElements()) {
  				keyAlias = (String) aliases.nextElement();
  				// 获取CA私钥
  				priKey = (PrivateKey) (keystoreCA.getKey(keyAlias,
  						rsaPassword.toCharArray()));
  				if (priKey != null) {
  					certMap.put("PrivateKey", priKey);
  					break;
  				}
  			}
  		}
  	} catch (Exception e) {
  		if (ins != null)
  			ins.close();
  		throw e;
  	} finally {
  		if (ins != null) {
  			ins.close();
  		}
  	}
  
  	return priKey;
  }
  

  }