java 如何实现判断一个对象所有的属性是否为空
能适配所有类型的:
Person person = new Person();
person.setId(0);
// --- true
Person person = null;
// --- true
Person person = new Person();
person.setName("xxx");
// --- false
Person person = new Person();
person.setName("");
// --- true
类似这个效果的...自己写了个类,只能对string判断:
package utils;
import java.lang.reflect.Field;
import java.lang.reflect.Method;
/**
* Created by weiyang on 2015/2/10.
*/
public class BeanUtils {
public static boolean checkFieldValueNull(Object bean) {
boolean result = true;
if (bean == null) {
return true;
}
Class<?> cls = bean.getClass();
Method[] methods = cls.getDeclaredMethods();
Field[] fields = cls.getDeclaredFields();
for (Field field : fields) {
try {
String fieldGetName = parGetName(field.getName());
if (!checkGetMet(methods, fieldGetName)) {
continue;
}
Method fieldGetMet = cls.getMethod(fieldGetName, new Class[]{});
Object fieldVal = fieldGetMet.invoke(bean, new Object[]{});
if (fieldVal != null) {
if ("".equals(fieldVal)) {
result = true;
} else {
result = false;
}
}
} catch (Exception e) {
continue;
}
}
return result;
}
/**
* 拼接某属性的 get方法
*
* @param fieldName
* @return String
*/
public static String parGetName(String fieldName) {
if (null == fieldName || "".equals(fieldName)) {
return null;
}
int startIndex = 0;
if (fieldName.charAt(0) == '_')
startIndex = 1;
return "get"
+ fieldName.substring(startIndex, startIndex + 1).toUpperCase()
+ fieldName.substring(startIndex + 1);
}
/**
* 判断是否存在某属性的 get方法
*
* @param methods
* @param fieldGetMet
* @return boolean
*/
public static boolean checkGetMet(Method[] methods, String fieldGetMet) {
for (Method met : methods) {
if (fieldGetMet.equals(met.getName())) {
return true;
}
}
return false;
}
}
阿暮暮3号
9 years, 9 months ago