降压反射的机制及意义 Java反射机制获取内部类的静态成员

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 = apache lucene document Field Index class;

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

　　Object indexDeclareFieldType = indexDeclareField get(cls);

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

　　//运行时调用Field Store类型

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

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

　　Object indexStoreDeclareField = indexDeclareField get(cls);