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标题: Java反射机制获取内部类的静态成员 [打印本页]

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作者: HM代景康    时间: 2013-9-29 20:02
标题: Java反射机制获取内部类的静态成员
最近需要些一个可配置的索引构建程序，需要在运行时调用Lucene包的如下类及其成员：

　　引用

　　Nested Class Summary

　　static class Field.Index

　　Specifies whether and how a field should be indexed.

　　static class Field.Store

　　Specifies whether and how a field should be stored.

　　static class Field.TermVector

　　Specifies whether and how a field should have term vectors.

　　lucene api中称之为Nested Class，意为嵌套类，而嵌套类内部的File.Index的成员又是静态成员。

　　引用

　　Field Summary

　　static Field.Index ANALYZED

　　Index the tokens produced by running the field's value through an Analyzer.

　　static Field.Index ANALYZED_NO_NORMS

　　Expert: Index the tokens produced by running the field's value through an Analyzer, and also separately disable the storing of norms.

　　static Field.Index NO

　　Do not index the field value.

　　static Field.Index NO_NORMS

　　Deprecated. This has been renamed to NOT_ANALYZED_NO_NORMS

　　static Field.Index NOT_ANALYZED

　　Index the field's value without using an Analyzer, so it can be searched.

　　static Field.Index NOT_ANALYZED_NO_NORMS

　　Expert: Index the field's value without an Analyzer, and also disable the storing of norms.

　　static Field.Index TOKENIZED

　　Deprecated. this has been renamed to ANALYZED

　　static Field.Index UN_TOKENIZED

　　Deprecated. This has been renamed to NOT_ANALYZED

　　一个棘手的问题，如果获得这些内部静态成员？

　　最后采用了如下方法：

　　//运行时调用Filed.Index类型

　　Java代码

　　Class<?> cls = org.apache.lucene.document.Field.Index.class;

　　java.lang.reflect.Field indexDeclareField = cls.getDeclaredField(field.getIndex());

　　Object indexDeclareFieldType = indexDeclareField.get(cls);

　　org.apache.lucene.document.Field.Index filedIndex = (org.apache.lucene.document.Field.Index)indexDeclareFieldType;

　　//运行时调用Field.Store类型

　　Class<?> clsStore = org.apache.lucene.document.Field.Index.class;

　　java.lang.reflect.Field storeDeclareField = cls.getDeclaredField(field.getIndex());

　　Object indexStoreDeclareField = indexDeclareField.get(cls);

　　org.apache.lucene.document.Field.Store filedStore = (org.apache.lucene.document.Field.Store)indexStoreDeclareField;

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