Map对象与实体类Object对象转换

<dependency>
    <groupId>com.alibaba</groupId>
    <artifactId>fastjson</artifactId>
    <version>1.1.46.sec01</version>
</dependency>

/**
 * 将Map转换为对象
 * @param paramMap
 * @param cls
 * @return
 */
public static <T> T parseMap2Object(Map<String, Object> paramMap, Class<T> cls) {
    // return JSON.parseObject(JSON.toJSONString(Map<String, ? extends Object>), Class<T> cls);
  return JSONObject.parseObject(JSONObject.toJSONString(paramMap), cls);
}

BeanUtils.populate(Object bean, Map<String, ? extends Object> properties)

public static Object mapToObject(Map<String, Object> map, Class<?> beanClass) throws Exception {    
    if (map == null)  
        return null;  
    Object obj = beanClass.newInstance();  
    org.apache.commons.beanutils.BeanUtils.populate(obj, map);  
    return obj;  
}    
public static Map<?, ?> objectToMap(Object obj) {  
    if(obj == null)  
        return null;   
    return new org.apache.commons.beanutils.BeanMap(obj);  
}  

public static Object mapToObject(Map<String, Object> map, Class<?> beanClass) throws Exception {    
    if (map == null)   
        return null;    
    Object obj = beanClass.newInstance();  
    BeanInfo beanInfo = Introspector.getBeanInfo(obj.getClass());    
    PropertyDescriptor[] propertyDescriptors = beanInfo.getPropertyDescriptors();    
    for (PropertyDescriptor property : propertyDescriptors) {  
        Method setter = property.getWriteMethod();    
        if (setter != null) {  
            setter.invoke(obj, map.get(property.getName()));   
        }  
    }  
    return obj;  
}    
public static Map<String, Object> objectToMap(Object obj) throws Exception {    
    if(obj == null)  
        return null;      
    Map<String, Object> map = new HashMap<String, Object>();   
    BeanInfo beanInfo = Introspector.getBeanInfo(obj.getClass());    
    PropertyDescriptor[] propertyDescriptors = beanInfo.getPropertyDescriptors();    
    for (PropertyDescriptor property : propertyDescriptors) {    
        String key = property.getName();    
        if (key.compareToIgnoreCase("class") == 0) {   
            continue;  
        }  
        Method getter = property.getReadMethod();  
        Object value = getter!=null ? getter.invoke(obj) : null;  
        map.put(key, value);  
    }    
    return map;  
} 

public static Object mapToObject(Map<String, Object> map, Class<?> beanClass) throws Exception {    
    if (map == null)  
        return null;    
    Object obj = beanClass.newInstance();  
    Field[] fields = obj.getClass().getDeclaredFields();   
    for (Field field : fields) {    
        int mod = field.getModifiers();    
        if(Modifier.isStatic(mod) || Modifier.isFinal(mod)){    
            continue;    
        }    
        field.setAccessible(true);    
        field.set(obj, map.get(field.getName()));   
    }   
    return obj;    
}    
public static Map<String, Object> objectToMap(Object obj) throws Exception {    
    if(obj == null){    
        return null;    
    }   
    Map<String, Object> map = new HashMap<String, Object>();    
    Field[] declaredFields = obj.getClass().getDeclaredFields();    
    for (Field field : declaredFields) {    
        field.setAccessible(true);  
        map.put(field.getName(), field.get(obj));  
    }    
    return map;  
}

/**
 * 利用反射将map集合封装成bean对象
 * 
 * @param params
 * @param clazz
 * @return
 */
public static <T> T mapToBean(Map<String, Object> map, Class<?> clazz) throws Exception {
  Object obj = clazz.newInstance();
  if (map != null && !map.isEmpty() && map.size() > 0) {
    for (Map.Entry<String, Object> entry : map.entrySet()) {
      String propertyName = entry.getKey();   // 属性名
      Object value = entry.getValue();    // 属性值
      String setMethodName = "set" + propertyName.substring(0, 1).toUpperCase() + propertyName.substring(1);
      Field field = getClassField(clazz, propertyName); //获取和map的key匹配的属性名称
      if (field == null){
        continue;
      }
      Class<?> fieldTypeClass = field.getType();
      value = convertValType(value, fieldTypeClass);
      try {
        clazz.getMethod(setMethodName, field.getType()).invoke(obj, value);
      } catch (NoSuchMethodException e) {
        e.printStackTrace();
      }
    }
  }
  return (T) obj;
}
/**
 * 根据给定对象类匹配对象中的特定字段
 * @param clazz
 * @param fieldName
 * @return
 */
private static Field getClassField(Class<?> clazz, String fieldName) {
  if (Object.class.getName().equals(clazz.getName())) {
    return null;
  }
  Field[] declaredFields = clazz.getDeclaredFields();
  for (Field field : declaredFields) {
    if (field.getName().equals(fieldName)) {
      return field;
    }
  }
  Class<?> superClass = clazz.getSuperclass();  //如果该类还有父类，将父类对象中的字段也取出
  if (superClass != null) {           //递归获取
    return getClassField(superClass, fieldName);
  }
  return null;
}
/**
 * 将map的value值转为实体类中字段类型匹配的方法
 * @param value
 * @param fieldTypeClass
 * @return
 */
private static Object convertValType(Object value, Class<?> fieldTypeClass) {
  Object retVal = null;
  if (Long.class.getName().equals(fieldTypeClass.getName())
      || long.class.getName().equals(fieldTypeClass.getName())) {
    retVal = Long.parseLong(value.toString());
  } else if (Integer.class.getName().equals(fieldTypeClass.getName())
      || int.class.getName().equals(fieldTypeClass.getName())) {
    retVal = Integer.parseInt(value.toString());
  } else if (Float.class.getName().equals(fieldTypeClass.getName())
      || float.class.getName().equals(fieldTypeClass.getName())) {
    retVal = Float.parseFloat(value.toString());
  } else if (Double.class.getName().equals(fieldTypeClass.getName())
      || double.class.getName().equals(fieldTypeClass.getName())) {
    retVal = Double.parseDouble(value.toString());
  } else {
    retVal = value;
  }
  return retVal;
}
/**
 * 对象转map
 * @param obj
 * @return
 */
private static Map<String, Object> objToMap(Object obj) {
  Map<String, Object> map = new HashMap<String, Object>();
  Field[] fields = obj.getClass().getDeclaredFields();  // 获取f对象对应类中的所有属性域
  for (int i = 0, len = fields.length; i < len; i++) {
    String varName = fields[i].getName();
    varName = varName.toLowerCase();          // 将key置为小写，默认为对象的属性
    try {
      boolean accessFlag = fields[i].isAccessible();  // 获取原来的访问控制权限
      fields[i].setAccessible(true);          // 修改访问控制权限
      Object o = fields[i].get(obj);          // 获取在对象f中属性fields[i]对应的对象中的变量
      if (o != null){
        map.put(varName, o.toString());
      }
      fields[i].setAccessible(accessFlag);      // 恢复访问控制权限
    } catch (IllegalArgumentException ex) {
      ex.printStackTrace();
    } catch (IllegalAccessException ex) {
      ex.printStackTrace();
    }
  }
  return map;
}