top.hmtools.security.MD5Tools Maven / Gradle / Ivy
package top.hmtools.security;
import java.io.File;
import java.io.FileInputStream;
import java.io.FileNotFoundException;
import java.io.IOException;
import java.math.BigInteger;
import java.nio.MappedByteBuffer;
import java.nio.channels.FileChannel;
import java.security.MessageDigest;
import java.security.NoSuchAlgorithmException;
import top.hmtools.io.NioFileTools;
/**
* MD5算法工具类
* @author Hybomyth
* 创建日期：2016-12-11下午4:06:30
*/
public class MD5Tools {
/**
* 获得 字节数组 的MD5加密值，结果为英文字母小写
* @param bytes
* @return
*/
public final static String getLowMD5Str(byte[] bytes) {
try {
// 获得MD5摘要算法的 MessageDigest 对象
MessageDigest mdInst = MessageDigest.getInstance("MD5");
// 使用指定的字节更新摘要
mdInst.update(bytes);
// 获得密文
BigInteger bi = new BigInteger(1, mdInst.digest());
return bi.toString(16);
} catch (Exception e) {
e.printStackTrace();
return null;
}
}
/**
* 获得 字符串 的MD5加密值，结果为英文字母小写
* @param str
* @return
*/
public final static String getLowMD5Str(String str) {
return getLowMD5Str(str.getBytes());
}
/**
* 通过NIO读取文件，并计算出其MD5值,结果为英文字母小写
* @param file
* @return
* @throws IOException
*/
public static String getLowMd5ByFileNio(File file) throws IOException{
byte[] bytesTmp = NioFileTools.readOneFileToByte(file);
return getLowMD5Str(bytesTmp);
}
/**
* 通过IO读取文件，并计算出其MD5值，结果为英文字母小写
* @param file
* @return
*/
public static String getLowMd5ByFileIo(File file){
String value = null;
FileInputStream in = null;
try {
in = new FileInputStream(file);
MappedByteBuffer byteBuffer = in.getChannel().map(FileChannel.MapMode.READ_ONLY, 0, file.length());
MessageDigest md5 = MessageDigest.getInstance("MD5");
// while(byteBuffer.hasRemaining()){//打印字节码值
// byte b = byteBuffer.get();
// System.out.print(b+" ");
// }
// byteBuffer.flip();//重置，使其进入输出准备就绪状态
md5.update(byteBuffer);
BigInteger bi = new BigInteger(1, md5.digest());
value = bi.toString(16);
} catch (Exception e) {
e.printStackTrace();
} finally {
if(null != in) {
try {
in.close();
} catch (IOException e) {
e.printStackTrace();
}
}
}
return value;
}
/**
* 获取大容量文件的MD5值，结果中的英文字母为小写
* @param pathname
* @return
*/
public static String getLowMd5ByBigFile(String pathname){
File file = new File(pathname);
return getLowMd5ByBigFile(file);
}
/**
* 获取大容量文件的MD5值，结果中的英文字母为小写
* @param file
* @return
*/
public static String getLowMd5ByBigFile(File file){
FileInputStream fileInputStream = null;
try {
MessageDigest mdInst = MessageDigest.getInstance("MD5");
fileInputStream = new FileInputStream(file);
byte[] buffer = new byte[8192];
int length;
while ((length = fileInputStream.read(buffer)) != -1) {
mdInst.update(buffer, 0, length);
}
BigInteger bi = new BigInteger(1, mdInst.digest());
return bi.toString(16);
} catch (FileNotFoundException e) {
e.printStackTrace();
return null;
} catch (IOException e) {
e.printStackTrace();
return null;
} catch (NoSuchAlgorithmException e) {
e.printStackTrace();
return null;
} finally {
try {
if (fileInputStream != null)
fileInputStream.close();
} catch (IOException e) {
e.printStackTrace();
}
}
}
}