java明文解密源代码 java 加解密开源工具类( 七 )


System out println(en)
System out println(decrypt(en))
}
lishixinzhi/Article/program/Java/hx/201311/26449
求java加密源代码(MD5,base64)import java.security.*;
import javax.crypto.*;
/**
* 本例解释如何利用DES私钥加密算法加解密
*
* @author Devon
* @version 1.0 04/03/10
*/
public class SingleKeyExample {
public static void main(String[] args) {
try {
String algorithm = "DES"; //定义加密算法,可用 DES,DESede,Blowfish
String message = "Hello World. 这是待加密的信息";
// 生成个DES密钥
KeyGenerator keyGenerator = KeyGenerator.getInstance(algorithm);
keyGenerator.init(56); //选择DES算法,密钥长度必须为56位
Key key = keyGenerator.generateKey(); //生成密钥
// 生成Cipher对象
Cipher cipher = Cipher.getInstance("DES");
//用密钥加密明文(message),生成密文(cipherText)
cipher.init(Cipher.ENCRYPT_MODE, key);//操作模式为加密(Cipher.ENCRYPT_MODE),key为密钥
byte[] cipherText = cipher.doFinal(message.getBytes());//得到加密后的字节数组
System.out.println("加密后的信息: " + new String(cipherText));
//用密钥加密明文(plainText),生成密文(cipherByte)
cipher.init(Cipher.DECRYPT_MODE, key);//操作模式为解密,key为密钥
byte[] sourceText = cipher.doFinal(cipherText); //获得解密后字节数组
System.out.println("解密后的信息: " + new String(sourceText));
} catch (Exception ex) {
ex.printStackTrace();
}
}
}
/**
* @author Devon
*/
import java.security.*;
import java.security.spec.*;
import javax.crypto.*;
public class PairKeyExample {
public static void main(String argv[]) {
try {
String algorithm = "RSA"; //定义加密算法,可用 DES,DESede,Blowfish
String message = "张三 , 你好,我是李四";
//产生张三的密钥对(keyPairZhang)
KeyPairGenerator keyGeneratorZhang =
KeyPairGenerator.getInstance(algorithm);//指定采用的算法
keyGeneratorZhang.initialize(1024); //指定密钥长度为1024位
KeyPair keyPairZhang = keyGeneratorZhang.generateKeyPair(); //产生密钥对
System.out.println("生成张三的公钥对");
// 张三生成公钥(publicKeyZhang)并发送给李四,这里发送的是公钥的数组字节
byte[] publicKeyZhangEncode = keyPairZhang.getPublic().getEncoded();
//通过网络或磁盘等方式,把公钥编码传送给李四
//李四接收到张三编码后的公钥,将其解码
KeyFactory keyFacoryLi = KeyFactory.getInstance(algorithm);//得到KeyFactory对象
X509EncodedKeySpec x509KeySpec =
new X509EncodedKeySpec(publicKeyZhangEncode);//公钥采用X.509编码
PublicKey publicKeyZhang = keyFacoryLi.generatePublic(x509KeySpec); //将公钥的KeySpec对象转换为公钥
System.out.println("李四成功解码,得到张三的公钥");
//李四用张三的公钥加密信息 , 并发送给李四
Cipher cipher = Cipher.getInstance("RSA/ECB/PKCS1Padding");//得到Cipher对象
cipher.init(Cipher.ENCRYPT_MODE, publicKeyZhang);//用张三的公钥初始化Cipher对象
byte[] cipherMessage = cipher.doFinal(message.getBytes());//得到加密信息
System.out.println("加密后信息:" + new String(cipherMessage));
System.out.println("加密完成,发送给李四...");
//张三用自己的私钥解密从李四处收到的信息
cipher.init(Cipher.DECRYPT_MODE, keyPairZhang.getPrivate()); //张三用其私钥初始化Cipher对象
byte[] originalMessage = cipher.doFinal(cipherMessage);//得到解密后信息
System.out.println("张三收到信息,解密后为:" + new String(originalMessage));
} catch (Exception ex) {
ex.printStackTrace();
}

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