循环Java类中的所有字段 [英] Loop over all fields in a Java class
本文介绍了循环Java类中的所有字段的处理方法,对大家解决问题具有一定的参考价值,需要的朋友们下面随着小编来一起学习吧!
问题描述
我有一个具有 Fields
的Java类。
lthe字段,并为无效的那些做一些事情。
例如如果我的类是:
public class ClassWithStuff {
public int inty;
public stringy;
public Stuff;
//更多字段
}
make a ClassWithStuff
对象,我想去遍历类中的所有字段。类似这样的:
for(int i = 0; i< ClassWithStuff.getFields()。size(); i ++ ){
//对每一个进行操作
}
c> ]
ClasWithStuff myStuff = new ClassWithStuff();
Field [] fields = myStuff.getClass()。getDeclaredFields();
for(Field f:fields){
Class t = f.getType();
Object v = f.get(o);
if(t == boolean.class& amp; Boolean.FALSE.equals(v))
//找到默认值
else if(t.isPrimitive()&& ((Number)v).doubleValue()== 0)
//找到默认值
else if(!t.isPrimitive()&& v == null)
/ /找到默认值
}
(http://docs.oracle.com/javase/1.5.0/docs/api/java/lang/Class.html )
I have a Java class that has a number of Fields
.
I would like to Loop over al lthe fields and do something for the one's that are null.
For example if my class is:
public class ClassWithStuff {
public int inty;
public stringy;
public Stuff;
//many more fields
}
In another location, I'd make a ClassWithStuff
object and I would like to go though all the fields in the class. Kind of like this:
for (int i = 0; i < ClassWithStuff.getFields().size(); i++) {
//do stuff with each one
}
Is there any way for me to achieve this?
解决方案
Use getDeclaredFields
on [Class]
ClasWithStuff myStuff = new ClassWithStuff();
Field[] fields = myStuff.getClass().getDeclaredFields();
for(Field f : fields){
Class t = f.getType();
Object v = f.get(o);
if(t == boolean.class && Boolean.FALSE.equals(v))
// found default value
else if(t.isPrimitive() && ((Number) v).doubleValue() == 0)
// found default value
else if(!t.isPrimitive() && v == null)
// found default value
}
(http://docs.oracle.com/javase/1.5.0/docs/api/java/lang/Class.html)
这篇关于循环Java类中的所有字段的文章就介绍到这了,希望我们推荐的答案对大家有所帮助,也希望大家多多支持IT屋!
查看全文