如何让Java反映出超类中的字段？不仅仅是实际的课程 [英] How to get Java reflect to spot fields in the super class? not just the actual class

问题描述

我最近改变了我的模式所以我的类继承自超类，问题是我的比较方法生成审计日志，使用Java反射，现在只循环遍历子类的字段，而不是超类，有没有办法获得所有的FIELDS？或者我是否需要将其投入超类......？

I've recently changed my schema a bit so my classes inherit from a super class, problem is my comparison method which generates an audit log, using Java reflect, is now only looping through the fields of the child class, not the superclass, is there a way to get all the FIELDS? or do I need to cast it into the super class.....?

以下是我的方法：

public static <T> String GenerateChangeLogForEntity(T old, T updated) {
        String text = "";
        try {
            Field[] fields = old.getClass().getDeclaredFields();
            if(fields != null) {
                BaseController.getLogger().info("Z1 num fields:"+fields.length);
                for (Field field : fields) {
                    if(field.isAnnotationPresent(Column.class)) {
                        String fieldName = field.getName();
                        BaseController.getLogger().info(field.getName());
                        if(field.isAnnotationPresent(Variation.class)) {
                            Variation v = field.getAnnotation(Variation.class);
                            fieldName = v.friendlyName();
                        }
                        field.setAccessible(true);
                        if(field.get(old) != null && field.get(updated) != null) {
                            if(!(field.get(old)).equals(field.get(updated))) {
                                text += "<p><span class=\"field-name\">"+fieldName+"</span> changed from: <strong>"+GetFriendlyFieldValueForChangeLog(field.get(old))+"</strong>  to: <strong>"+GetFriendlyFieldValueForChangeLog(field.get(updated)) + "</strong></p>";
                            }
                        }
                        if(field.get(old) == null && field.get(updated) != null) {
                            text += "<p><span class=\"field-name\">"+fieldName+"</span> changed from: <strong>empty</strong> to: <strong>"+GetFriendlyFieldValueForChangeLog(field.get(updated)) + "</strong></p>";
                        }
                        if(field.get(old) != null && field.get(updated) == null) {
                            text += "<p><span class=\"field-name\">"+fieldName+"</span> changed from: <strong>"+GetFriendlyFieldValueForChangeLog(field.get(updated))+"</strong> to <strong>empty</strong>" + "</p>";
                        }
                        field.setAccessible(false);
                    }
                }
            }
        } catch(IllegalAccessException e) {}
        return text;
    }

推荐答案

您可以使用 this.getClass（）。getSuperClass（），直到此 getSuperClass（）方法返回null以获取父字段。

You can use this.getClass().getSuperClass() until this getSuperClass() method returns null to get the parent fields.

所以，最好的方法是将代码分解。实现一个方法，将 Field 列表作为参数并在其中执行逻辑部分，以及通过搜索字段的main方法（ superClass！= null） loop。

So, the best would be that you factorize your code. Implement one method that takes a list of Field as parameter and do your logical part within it, and a main method that search for fields through a while(superClass != null) loop.

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