-
Reflection依赖了谷歌的Guava包，出现此问题可能是因为缺少Guava或者包冲突。
- Reflections 0.9.11用的是Guava 20，Reflection 0.9.10用的是Guava 18，
- 如果需要用Guava 18，则只能用Reflection 0.9.10版本。
- 依赖
org.reflections reflections 0.9.11 -
Reflection框架可以：
- 获取某个类型的全部子类
- 只要类型、构造器、方法，字段上带有特定注解，便能获取带有这个注解的全部信息（类型、构造器、方法，字段）
- 获取所有能匹配某个正则表达式的资源
- 获取所有带有特定签名的方法，包括参数，参数注解，返回类型
- 获取所有方法的名字
- 获取代码里所有字段、方法名、构造器的使用
示例
import com.coding.springboot.domain.Docker;
import com.coding.springboot.domain.User;
import com.google.common.base.Stopwatch;
import org.junit.Test;
import org.reflections.scanners.FieldAnnotationsScanner;
import org.reflections.scanners.MethodAnnotationsScanner;
import org.reflections.scanners.MethodParameterScanner;
import org.reflections.scanners.ResourcesScanner;
import org.reflections.util.ClasspathHelper;
import org.reflections.util.ConfigurationBuilder;
import org.springframework.beans.factory.BeanFactory;
import org.springframework.stereotype.Service;
import org.springframework.web.bind.annotation.PathVariable;
import org.springframework.web.bind.annotation.RequestMapping;
import javax.persistence.Column;
import javax.persistence.Id;
import java.io.InputStream;
import java.lang.reflect.*;
import java.util.Collection;
import java.util.List;
import java.util.Set;
import java.util.regex.Pattern;
/**
* @author micocube
* projectName: utils4j
* packageName: com.coding.reflect
* email: [email protected]
* createTime: 2019-07-05 16:20
* version: 0.1
* description: reflection 框架
* Reflection依赖了谷歌的Guava包，出现此问题可能是因为缺少Guava或者包冲突。
* Reflections 0.9.11用的是Guava 20，Reflection 0.9.10用的是Guava 18，
* 如果需要用Guava 18，则只能用Reflection 0.9.10版本。
*
* org.reflections
* reflections
* 0.9.11
*
*
*
* 1.获取某个类型的全部子类
* 2.只要类型、构造器、方法，字段上带有特定注解，便能获取带有这个注解的全部信息（类型、构造器、方法，字段）
* 3.获取所有能匹配某个正则表达式的资源
* 4.获取所有带有特定签名的方法，包括参数，参数注解，返回类型
* 5.获取所有方法的名字
* 6.获取代码里所有字段、方法名、构造器的使用
*/
public class Reflections {
//获取所有Inputstream的子类，限定只扫包前缀为“java”的，也就是jdk自带的
@Test
public void testPackage(){
org.reflections.Reflections reflections = new org.reflections.Reflections("java.");
Stopwatch stopwatch = Stopwatch.createStarted();
Set> allTypes = reflections.getSubTypesOf(InputStream.class);
System.out.println(stopwatch.toString());
for (Class type : allTypes) {
System.out.println("Found:"+type.getName());
}
}
// com.coding 包下的所有带有service注解的类
@Test
public void testAnnotationType(){
org.reflections.Reflections reflections = new org.reflections.Reflections("com.coding");
Stopwatch stopwatch = Stopwatch.createStarted();
Set> classes = reflections.getTypesAnnotatedWith(Service.class);
System.out.println(stopwatch.toString());
for (Class type : classes) {
System.out.println("Found:"+type.getName());
}
}
// 假如想扫描整个工程的类，直接new一个不带参数的Reflections就好。
// 值得一提的是，这东西在扫描的时候，连依赖的jar包都不放过。以Spring框架的BeanFactory为例：
@Test
public void testSubType2(){
org.reflections.Reflections reflections = new org.reflections.Reflections();
Set> classes = reflections.getSubTypesOf(BeanFactory.class);
for(Class clazz : classes) {
//logger.info(clazz.getName());
System.out.println("Found: " + clazz.getName());
}
}
// 所有带RequestMapping注解的方法
@Test
public void testAnnotationMethod(){
org.reflections.Reflections reflections = new org.reflections.Reflections(
new ConfigurationBuilder()
.setUrls(ClasspathHelper.forPackage("com.coding"))
.addScanners(new MethodAnnotationsScanner()));
Set annotatedWith = reflections.getMethodsAnnotatedWith(RequestMapping.class);
for(Method p : annotatedWith) {
//logger.info(clazz.getName());
System.out.println("Found: " + p.getName());
}
}
// 所有properties文件
@Test
public void testResource(){
org.reflections.Reflections reflections = new org.reflections.Reflections(
new ConfigurationBuilder()
.setUrls(ClasspathHelper.forPackage("com.coding"))
.addScanners(new ResourcesScanner()));
Set properties =
reflections.getResources(Pattern.compile(".*\\.properties"));
for(String p : properties) {
//logger.info(clazz.getName());
System.out.println("Found: " + p);
}
}
// 所有带Deprecated注解的构造方法
@Test
public void testAnnotationConstractor(){
org.reflections.Reflections reflections = new org.reflections.Reflections(
new ConfigurationBuilder()
.setUrls(ClasspathHelper.forPackage("com.coding"))
.addScanners(new MethodAnnotationsScanner()));
Set annotated = reflections.getConstructorsAnnotatedWith(Deprecated.class);
for(Constructor p : annotated) {
//logger.info(clazz.getName());
System.out.println("Found: " + p.getName());
}
}
// 所有带Id注解的构造方法
@Test
public void testAnnotationField(){
org.reflections.Reflections reflections = new org.reflections.Reflections(
new ConfigurationBuilder()
.setUrls(ClasspathHelper.forPackage("com.coding"))
.addScanners(new FieldAnnotationsScanner()));
Set annotated = reflections.getFieldsAnnotatedWith(Id.class);
for(Field p : annotated) {
//logger.info(clazz.getName());
System.out.println("Found: " + p.getName());
}
}
// MethodParameterScanner 方法参数扫描器
@Test
public void testMethodParameter(){
org.reflections.Reflections reflections = new org.reflections.Reflections(
new ConfigurationBuilder()
.setUrls(ClasspathHelper.forPackage("com.coding"))
.addScanners(new MethodParameterScanner()));
//MethodParameterScanner
Set someMethods =
reflections.getMethodsMatchParams(String[].class);
Set voidMethods =
reflections.getMethodsReturn(User.class);
Set pathParamMethods =
reflections.getMethodsWithAnyParamAnnotated(PathVariable.class);
for(Method p : someMethods) {
//logger.info(clazz.getName());
System.out.println("方法参数符合String[]的class：Found: " + p.getName());
}
for(Method p : voidMethods) {
//logger.info(clazz.getName());
System.out.println("返回值为User的方法：Found: " + p.getName());
}
for(Method p : pathParamMethods) {
//logger.info(clazz.getName());
System.out.println("参数带有PathVariable注解的方法：Found: " + p.getName());
}
}
// 测试框架自带的工具类
@Test
public void testReflectionUtils(){
// 所有get方法
Set getters = org.reflections.ReflectionUtils.getAllMethods(User.class,
org.reflections.ReflectionUtils.withModifier(Modifier.PUBLIC),
org.reflections.ReflectionUtils.withPrefix("get"),
org.reflections.ReflectionUtils.withParametersCount(0));
// 参数是Collection的子类，返回值是boolean
Set listMethodsFromCollectionToBoolean =
org.reflections.ReflectionUtils.getAllMethods(List.class,
org.reflections.ReflectionUtils.withParametersAssignableTo(Collection.class),
org.reflections.ReflectionUtils.withReturnType(boolean.class));
// field 带有Column注解，类型是String的子类
Set fields = org.reflections.ReflectionUtils.getAllFields(Docker.class,
org.reflections.ReflectionUtils.withAnnotation(Column.class),
org.reflections.ReflectionUtils.withTypeAssignableTo(String.class));
getters.forEach(get->System.out.println("getter:"+get));
listMethodsFromCollectionToBoolean.forEach(get->System.out.println("listMethodsFromCollectionToBoolean:"+get));
fields.forEach(get->System.out.println("fields:"+get));
}
}
转自：https://www.jianshu.com/p/49199793aff3