使用反射比较字段值 [英] Comparing field values using reflection

问题描述

我试图以通用方式比较两个不同对象的字段值。我有一个函数（如下所示），它接收两个对象，然后获取字段，然后比较循环中的字段，如果它们不相同，则将字段添加到列表中 - 这是正确的方法吗？

I am trying to compare the field values of two different objects in a generic way. I have a function (seen below) that takes in two Objects and then gets the fields and then compares the fields in a loop and adds the fields to a list if they are not the same - is this the proper way to do this?

public void compareFields(Object qa, Object qa4) throws FieldsNotEqualException
{

  Field[] qaFields = qa.getClass().getFields();
  Field[] qa4Fields = qa4.getClass().getFields();

  for(Field f:qaFields) 
  { 

    for(Field f4:qa4Fields)
    {
       if(f4.equals(f))
       {
           found = true;
           break;
       }
       else
       {
           continue;
       }
    }
  }

 if(!found)
 {
    report.add(/*some_formatted_string*/) //some global list 
    throw new FieldsNotEqualException();
 }
}

我在谷歌搜索，我看到C＃就像一个PropertyInfo类 - Java有类似的东西吗？
另外，有没有办法像 f.getFieldValue（） - 我知道没有这样的方法，但也许有另一种方式??? / p>

I was googling and I saw that C# had like a PropertyInfo Class - does Java have anything like that? ALSO, is there a way to do like f.getFieldValue() -I know there is no method like this but maybe there is another way???

推荐答案

您可以查看org.apache.commons.lang.builder.EqualsBuilder，这将为您节省很多麻烦，如果你我想通过现场比较做一个领域。

You might check out org.apache.commons.lang.builder.EqualsBuilder which will save you a lot of this hassle if you're wanting to do a field by field comparison.

org.apache.commons.lang.builder.EqualsBuilder.reflectionEquals(Object, Object)

如果您想自己比较字段，请查看 java.lang.Class.getDeclaredFields（）这将为您提供包括非公共字段在内的所有字段。

If you're wanting to compare fields yourself, check out java.lang.Class.getDeclaredFields() which will give you all the fields including non-public fields.

要比较字段的值，请使用 f.get（qa）.equals（f.get（qa4））目前，您实际上是在比较字段实例而不是值。

To compare the value of the fields use f.get(qa).equals(f.get(qa4)) Currently, you are actually comparing the field instances and not the values.

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