java类扫描

 本文采用按照指定包扫描、按照指定注解类过滤的java类扫描

1. [代码]ClassScaner

package com.bswan;

import java.io.IOException;

import java.lang.annotation.Annotation;

import java.util.HashSet;

import java.util.LinkedList;

import java.util.List;

import java.util.Set;

import org.apache.log4j.Logger;

import org.springframework.beans.factory.BeanDefinitionStoreException;

import org.springframework.context.ResourceLoaderAware;

import org.springframework.core.io.Resource;

import org.springframework.core.io.ResourceLoader;

import org.springframework.core.io.support.PathMatchingResourcePatternResolver;

import org.springframework.core.io.support.ResourcePatternResolver;

import org.springframework.core.io.support.ResourcePatternUtils;

import org.springframework.core.type.classreading.CachingMetadataReaderFactory;

import org.springframework.core.type.classreading.MetadataReader;

import org.springframework.core.type.classreading.MetadataReaderFactory;

import org.springframework.core.type.filter.AnnotationTypeFilter;

import org.springframework.core.type.filter.TypeFilter;

import org.springframework.util.ClassUtils;

import org.springframework.util.SystemPropertyUtils;

import core.plugin.table.Table;

import core.route.Controllers;

@SuppressWarnings({ "rawtypes", "unchecked" })

public class ClassScaner implements ResourceLoaderAware {

/**

* log

*/

private static Logger logger = Logger.getLogger(ClassScaner.class);

private ResourcePatternResolver resourcePatternResolver = new PathMatchingResourcePatternResolver();

private final List<TypeFilter> includeFilters = new LinkedList<TypeFilter>();

private final List<TypeFilter> excludeFilters = new LinkedList<TypeFilter>();

private MetadataReaderFactory metadataReaderFactory = new CachingMetadataReaderFactory(

this.resourcePatternResolver);

public ClassScaner() {

}

public void setResourceLoader(ResourceLoader resourceLoader) {

this.resourcePatternResolver = ResourcePatternUtils

.getResourcePatternResolver(resourceLoader);

this.metadataReaderFactory = new CachingMetadataReaderFactory(

resourceLoader);

}

public final ResourceLoader getResourceLoader() {

return this.resourcePatternResolver;

}

public void addIncludeFilter(TypeFilter includeFilter) {

this.includeFilters.add(includeFilter);

}

public void addExcludeFilter(TypeFilter excludeFilter) {

this.excludeFilters.add(0, excludeFilter);

}

public void resetFilters(boolean useDefaultFilters) {

this.includeFilters.clear();

this.excludeFilters.clear();

}

public static Set<Class> scan(String basePackage,Class<? extends Annotation>... annotations) {

ClassScaner cs = new ClassScaner();

for (Class anno : annotations){

cs.addIncludeFilter(new AnnotationTypeFilter(anno));

}

return cs.doScan(basePackage);

}

public static Set<Class> scan(String[] basePackages,Class<? extends Annotation>... annotations) {

ClassScaner cs = new ClassScaner();

for (Class anno : annotations){

cs.addIncludeFilter(new AnnotationTypeFilter(anno));

}

Set<Class> classes = new HashSet<Class>();

for (String s : basePackages){

classes.addAll(cs.doScan(s));

}

return classes;

}

public Set<Class> doScan(String basePackage) {

Set<Class> classes = new HashSet<Class>();

try {

String packageSearchPath = ResourcePatternResolver.CLASSPATH_ALL_URL_PREFIX + ClassUtils.convertClassNameToResourcePath(SystemPropertyUtils.resolvePlaceholders(basePackage))+ "/**/*.class";

System.out.println(packageSearchPath);

Resource[] resources = this.resourcePatternResolver.getResources(packageSearchPath);

for (int i = 0; i < resources.length; i++) {

Resource resource = resources[i];

System.out.println(resource.getFilename());

if (resource.isReadable()) {

MetadataReader metadataReader = this.metadataReaderFactory.getMetadataReader(resource);

if ((includeFilters.size() == 0 && excludeFilters.size() == 0)|| matches(metadataReader)) {

try {

classes.add(Class.forName(metadataReader.getClassMetadata().getClassName()));

} catch (ClassNotFoundException e) {

logger.error(e.getMessage());

}

}

}

}

} catch (IOException ex) {

throw new BeanDefinitionStoreException(

"I/O failure during classpath scanning", ex);

}

return classes;

}

protected boolean matches(MetadataReader metadataReader) throws IOException {

for (TypeFilter tf : this.excludeFilters) {

if (tf.match(metadataReader, this.metadataReaderFactory)) {

return false;

}

}

for (TypeFilter tf : this.includeFilters) {

if (tf.match(metadataReader, this.metadataReaderFactory)) {

return true;

}

}

return false;

}

public static void main(String[] args) {

Set<Class> set = ClassScaner.scan("com.bswan", Table.class,Controllers.class);

for (Class class1 : set) {

System.out.println(class1.getName());

}

}

}