m-1

Author: weileifrank

.idea/workspace.xml

@@ -0,0 +1,76 @@
+package com.bupin.frank;
+
+import java.io.ByteArrayOutputStream;
+import java.io.FileInputStream;
+import java.security.MessageDigest;
+
+public class HashDemo {
+    public static void main(String[] args) throws Exception {
+        String input = "frank";
+        String md5 = getDigest(input, "MD5");
+        System.out.println("md5:"+md5);
+        String sha1 = getDigest(input, "SHA-1");
+        System.out.println("sha1:"+sha1);
+        String sha256 = getDigest(input, "SHA-256");
+        System.out.println("sha256:"+sha256);
+        String sha512 = getDigest(input, "SHA-512");
+        System.out.println("sha512:"+sha512);
+        String fileSha1 = getDigestFile("a.txt", "SHA-1");
+        System.out.println("fileSha1:"+fileSha1);
+
+    }
+
+    /**
+     * 获取消息摘要
+     *
+     * @param input     : 原文
+     * @param algorithm : 算法
+     * @return : 消息摘要
+     * @throws Exception
+     */
+    public static String getDigest(String input, String algorithm) throws Exception {
+        // 获取MessageDigest对象
+        MessageDigest messageDigest = MessageDigest.getInstance(algorithm);
+        // 生成消息摘要
+        byte[] digest = messageDigest.digest(input.getBytes());
+        return toHex(digest);
+
+    }
+
+    /**
+     *
+     * @param filePath 文件路径
+     * @param algorithm 算法
+     * @return 返回对应的哈希值
+     * @throws Exception
+     */
+    public static String getDigestFile(String filePath, String algorithm) throws Exception {
+        FileInputStream fis = new FileInputStream(filePath);
+        int len;
+        byte[] buffer = new byte[1024];
+        ByteArrayOutputStream baos = new ByteArrayOutputStream();
+        while ((len = fis.read(buffer)) != -1) {
+            baos.write(buffer, 0, len);
+        }
+        // 获取MessageDigest对象
+        MessageDigest messageDigest = MessageDigest.getInstance(algorithm);
+        // 生成消息摘要
+        byte[] digest = messageDigest.digest(baos.toByteArray());
+        return toHex(digest);
+
+    }
+
+    // 将字节数组转为16进制字符串
+    public static String toHex(byte[] digest) {
+        StringBuilder sb = new StringBuilder();
+        for (byte b : digest) {
+            int i = b & 0xff;
+            String s = Integer.toHexString(i);
+            if (s.length() == 1) {
+                s = "0" + s;
+            }
+            sb.append(s);
+        }
+        return sb.toString();
+    }
+}