blocks|key|143937|text|你的意思是像|type|unstyled|depth|inlineStyleRanges|entityRanges|data|143938|Field[]+fields+=+SomeClass.class.getDeclaredFields();|code-block|syntax|javascript|143939|entityMap^0|0|0^^$0|@$1|2|3|4|5|6|7|I|8|@]|9|@]|A|$]]|$1|B|3|C|5|D|7|J|8|@]|9|@]|A|$E|F]]|$1|G|3|-4|5|6|7|K|8|@]|9|@]|A|$]]]|H|$]]

Do you mean like

<pre><code>Field[] fields = SomeClass.class.getDeclaredFields();
</code></pre>

blocks|key|362126|text|可以使用Class的getDeclaredFields()方法获取所有字段。然后必须检查每个字段的修饰符，以找到私有字段：|type|unstyled|depth|inlineStyleRanges|offset|length|style|CODE|entityRanges|data|362127|List<Field>+privateFields+=+new+ArrayList<>();
Field[]+allFields+=+SomeClass.class.getDeclaredFields();
for+(Field+field+:+allFields)+{
++++if+(Modifier.isPrivate(field.getModifiers()))+{
++++++++privateFields.add(field);
++++}
}|code-block|syntax|javascript|362128|请注意，getDeclaredFields()不会返回继承的字段。|362129|最后，您将使用Field.getType()方法获取字段的类型。|362130|entityMap|0|LINK|mutability|MUTABLE|url|http://docs.oracle.com/javase/6/docs/api/java/lang/reflect/Field.html#getType%2528%2529^0|4|5|A|J|0|0|4|J|0|7|F|0|0^^$0|@$1|2|3|4|5|6|7|W|8|@$9|X|A|Y|B|C]|$9|Z|A|10|B|C]]|D|@]|E|$]]|$1|F|3|G|5|H|7|11|8|@]|D|@]|E|$I|J]]|$1|K|3|L|5|6|7|12|8|@$9|13|A|14|B|C]]|D|@]|E|$]]|$1|M|3|N|5|6|7|15|8|@]|D|@$9|16|A|17|1|18]]|E|$]]|$1|O|3|-4|5|6|7|19|8|@]|D|@]|E|$]]]|P|$Q|$5|R|S|T|E|$U|V]]]]

It is possible to obtain all fields with the method <code>getDeclaredFields()</code> of <code>Class</code>. Then you have to check the modifier of each fields to find the private ones:

<pre><code>List&lt;Field&gt; privateFields = new ArrayList&lt;&gt;();
Field[] allFields = SomeClass.class.getDeclaredFields();
for (Field field : allFields) {
 if (Modifier.isPrivate(field.getModifiers())) {
 privateFields.add(field);
 }
}
</code></pre>

Note that <code>getDeclaredFields()</code> will not return inherited fields.

Eventually, you get the type of the fields with the method <a href="http://docs.oracle.com/javase/6/docs/api/java/lang/reflect/Field.html#getType%28%29" rel="noreferrer">Field.getType()</a>.

blocks|key|362167|text|您可以使用Modifier来确定字段是否为私有字段。请务必使用getDeclaredFields方法以确保从类中检索私有字段，调用getFields将仅返回公共字段。|type|unstyled|depth|inlineStyleRanges|offset|length|style|CODE|entityRanges|data|362168|public+class+SomeClass+{

++++private+String+aaa;
++++private+Date+date;
++++private+double+ccc;
++++public+int+notPrivate;

++++public+static+void+main(String[]+args)+{
++++++++List<Field>+fields+=+getPrivateFields(SomeClass.class);
++++++++for(Field+field:+fields){
++++++++++++System.out.println(field.getName());
++++++++}
++++}

++++public+static+List<Field>+getPrivateFields(Class<?>+theClass){
++++++++List<Field>+privateFields+=+new+ArrayList<Field>();

++++++++Field[]+fields+=+theClass.getDeclaredFields();

++++++++for(Field+field:fields){
++++++++++++if(Modifier.isPrivate(field.getModifiers())){
++++++++++++++++privateFields.add(field);
++++++++++++}
++++++++}
++++++++return+privateFields;
++++}
}|code-block|syntax|javascript|362169|entityMap^0|5|8|V|H|1T|9|0|0^^$0|@$1|2|3|4|5|6|7|M|8|@$9|N|A|O|B|C]|$9|P|A|Q|B|C]|$9|R|A|S|B|C]]|D|@]|E|$]]|$1|F|3|G|5|H|7|T|8|@]|D|@]|E|$I|J]]|$1|K|3|-4|5|6|7|U|8|@]|D|@]|E|$]]]|L|$]]

You can use <code>Modifier</code> to determine if a field is private. Be sure to use the <code>getDeclaredFields</code> method to ensure that you retrieve private fields from the class, calling <code>getFields</code> will only return the public fields.

<pre><code>public class SomeClass {

 private String aaa;
 private Date date;
 private double ccc;
 public int notPrivate;

 public static void main(String[] args) {
 List&lt;Field&gt; fields = getPrivateFields(SomeClass.class);
 for(Field field: fields){
 System.out.println(field.getName());
 }
 }

 public static List&lt;Field&gt; getPrivateFields(Class&lt;?&gt; theClass){
 List&lt;Field&gt; privateFields = new ArrayList&lt;Field&gt;();

 Field[] fields = theClass.getDeclaredFields();

 for(Field field:fields){
 if(Modifier.isPrivate(field.getModifiers())){
 privateFields.add(field);
 }
 }
 return privateFields;
 }
}
</code></pre>

blocks|key|144039|text|尝试使用apache+commons-lang3中的FieldUtils：|type|unstyled|depth|inlineStyleRanges|offset|length|style|CODE|entityRanges|data|144040|FieldUtils.getAllFieldsList(Class<?>+cls)|code-block|syntax|javascript|144041|entityMap|0|LINK|mutability|MUTABLE|url|http://commons.apache.org/proper/commons-lang/apidocs/org/apache/commons/lang3/reflect/FieldUtils.html^0|Q|A|Q|A|0|0|0^^$0|@$1|2|3|4|5|6|7|S|8|@$9|T|A|U|B|C]]|D|@$9|V|A|W|1|X]]|E|$]]|$1|F|3|G|5|H|7|Y|8|@]|D|@]|E|$I|J]]|$1|K|3|-4|5|6|7|Z|8|@]|D|@]|E|$]]]|L|$M|$5|N|O|P|E|$Q|R]]]]

Try <a href="http://commons.apache.org/proper/commons-lang/apidocs/org/apache/commons/lang3/reflect/FieldUtils.html" rel="noreferrer"><code>FieldUtils</code></a> from apache commons-lang3:

<pre><code>FieldUtils.getAllFieldsList(Class&lt;?&gt; cls)
</code></pre>

blocks|key|362258|text|使用Java+8：|type|unstyled|depth|inlineStyleRanges|entityRanges|data|362259|Field[]+fields+=+String.class.getDeclaredFields();
List<Field>+privateFieldList+=+Arrays.asList(fields).stream().filter(field+->+Modifier.isPrivate(field.getModifiers())).collect(
++++++++Collectors.toList());|code-block|syntax|javascript|362260|entityMap^0|0|0^^$0|@$1|2|3|4|5|6|7|I|8|@]|9|@]|A|$]]|$1|B|3|C|5|D|7|J|8|@]|9|@]|A|$E|F]]|$1|G|3|-4|5|6|7|K|8|@]|9|@]|A|$]]]|H|$]]

Using Java 8 :

<pre><code>Field[] fields = String.class.getDeclaredFields();
List&lt;Field&gt; privateFieldList = Arrays.asList(fields).stream().filter(field -&gt; Modifier.isPrivate(field.getModifiers())).collect(
 Collectors.toList());
</code></pre>

I wonder is there a way to get all private fields of some class in java and their type.

For example lets suppose I have a class

<pre><code>class SomeClass {
 private String aaa;
 private SomeOtherClass bbb;
 private double ccc;
}
</code></pre>

Now I would like to get all private fields (<code>aaa</code>, <code>bbb</code>, <code>ccc</code>) of class <code>SomeClass</code> (Without knowing name of all fields upfront) and check their type.

Java reflection get all private fields

Java

我想知道有没有一种方法可以获取java中某个类的所有私有字段及其类型。例如，假设我有一个类class SomeClass {    private String aaa;    private SomeOtherClass bbb;    private double ccc;}现在，我想获取SomeClass类的所有...

问Java反射获取所有私有字段
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