必须要的jar：
<!-- https://mvnrepository.com/artifact/com.google.guava/guava -->
<dependency>
<groupId>com.google.guava</groupId>
<artifactId>guava</artifactId>
<version>19.0</version>
</dependency>
<!-- https://mvnrepository.com/artifact/com.google.code.gson/gson -->
<dependency>
<groupId>com.google.code.gson</groupId>
<artifactId>gson</artifactId>
<version>2.8.0</version>
</dependency>
工具类代码：
import java.io.File;
import java.io.IOException;
import java.lang.reflect.Field;
import java.nio.charset.Charset;
import java.util.List;
import java.util.Map;
import com.google.common.collect.Maps;
import com.google.common.hash.Funnel;
import com.google.common.hash.HashCode;
import com.google.common.hash.HashFunction;
import com.google.common.hash.Hasher;
import com.google.common.hash.Hashing;
import com.google.common.hash.PrimitiveSink;
import com.google.common.io.Files;
import com.google.gson.Gson;
public class Md5Util {
private static HashFunction hf = Hashing.md5();
private static Charset defaultCharset = Charset.forName("UTF-8");
private Md5Util() {
throw new AssertionError("不要实例化工具类哦");
}
public static String md5(String data) {
HashCode hash = hf.newHasher().putString(data, defaultCharset).hash();
return hash.toString();
}
public static String md5(String data, Charset charset, boolean isUpperCase) {
HashCode hash = hf.newHasher().putString(data, charset == null ? defaultCharset : charset).hash();
return isUpperCase ? hash.toString().toUpperCase() : hash.toString();
}
public static String md5(byte[] bytes, boolean isUpperCase) {
HashCode hash = hf.newHasher().putBytes(bytes).hash();
return isUpperCase ? hash.toString().toUpperCase() : hash.toString();
}
public static String md5(File sourceFile, boolean isUpperCase) {
HashCode hash = hf.newHasher().putObject(sourceFile, new Funnel<File>() {
private static final long serialVersionUID = 2757585325527511209L;
@Override
public void funnel(File from, PrimitiveSink into) {
try {
into.putBytes(Files.toByteArray(from));
} catch (IOException e) {
throw new RuntimeException(e);
}
}
}).hash();
return isUpperCase ? hash.toString().toUpperCase() : hash.toString();
}
/**
* 将其转换为json后，再进行md5
*
* @param object 数据源可以是任何类型的对象
* @param isUpperCase 结果是否大写
* @param charset 涉及到字符串时的操作编码，默认是utf-8
* @return
*/
public static String md5(Object object, boolean isUpperCase, Charset charset) {
Hasher hasher = hf.newHasher();
Gson gson = new Gson();
String json = gson.toJson(object);
HashCode hash = hasher.putString(json, charset == null ? defaultCharset : charset).hash();
return isUpperCase ? hash.toString().toUpperCase() : hash.toString();
}
/**
* @param object 只能是封装了数据的实体类，不可以是map，List等
* @param fieldNames 需要参与md5计算的字段属性名，如果该属性也是一个封住数据实体类话，.后跟上具体属性名即可。如：role.level.id
* @param isUpperCase 结果是否大写
* @param charset 涉及到字符串时的操作编码，默认是utf-8
* @return
*/
public static String md5(Object object, List<String> fieldNames, boolean isUpperCase, Charset charset) {
HashCode hash = hf.newHasher().putObject(object, new Funnel<Object>() {
private static final long serialVersionUID = -5236251432355557848L;
@Override
public void funnel(Object from, PrimitiveSink into) {
Map<String, Field> allField = getAllField(object);
for (String fieldName : fieldNames) {
try {
if (fieldName.contains(".")) {
handleDeepField(object, charset, into, allField, fieldName);
} else {
handleField(object, charset, into, allField, fieldName);
}
} catch (Exception e) {
throw new RuntimeException(e);
}
}
}
}).hash();
return isUpperCase ? hash.toString().toUpperCase() : hash.toString();
}
private static void handleDeepField(Object tempValue, Charset charset, PrimitiveSink into, Map<String, Field> tempAllField, String fieldName)
throws NoSuchFieldException, IllegalAccessException {
Field field = null;
String[] names = fieldName.split("\\.");
for (String name : names) {
field = tempAllField.get(name);
if (field == null) {
throw new NoSuchFieldException(fieldName);
}
field.setAccessible(true);
tempValue = field.get(tempValue);
field.setAccessible(false);
tempAllField = getAllField(tempValue);
}
stuffFieldValue(tempValue, charset, into);
}
private static void handleField(Object object, Charset charset, PrimitiveSink into, Map<String, Field> allField, String fieldName)
throws NoSuchFieldException, IllegalAccessException {
Field field = allField.get(fieldName);
if (field == null) {
throw new NoSuchFieldException(fieldName);
}
field.setAccessible(true);
Object tempValue = field.get(object);
stuffFieldValue(tempValue, charset, into);
field.setAccessible(false);
}
private static void stuffFieldValue(Object value, Charset charset, PrimitiveSink into) throws IllegalAccessException {
if (value instanceof Integer) {
into.putInt((int) value);
} else if (value instanceof Long) {
into.putLong((long) value);
} else if (value instanceof Float) {
into.putFloat((float) value);
} else if (value instanceof Double) {
into.putDouble((double) value);
} else if (value instanceof Short) {
into.putShort((short) value);
} else if (value instanceof Byte) {
into.putByte((byte) value);
} else if (value instanceof Boolean) {
into.putBoolean((boolean) value);
} else if (value instanceof Byte) {
into.putByte((byte) value);
} else if (value instanceof Character) {
into.putChar((char) value);
} else if (value instanceof String) {
into.putString((String) value, charset == null ? defaultCharset : charset);
} else {
throw new IllegalArgumentException(value.getClass() + " is not basic data type");
}
}
private static Map<String, Field> getAllField(Object object) {
Map<String, Field> fieldMap = Maps.newHashMap();
if (object.getClass().getName().equals(Object.class.getName())) {
return fieldMap;
}
Class<?> tempClass = object.getClass();
Field[] declaredFields = null;
while (true) {
declaredFields = tempClass.getDeclaredFields();
for (Field field : declaredFields) {
fieldMap.put(field.getName(), field);
}
tempClass = tempClass.getSuperclass();
if (tempClass.getName().equals(Object.class.getName())) {
break;
}
}
return fieldMap;
}
}