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我们可以通过反射，获取对应的运行时类中所有的属性、方法、构造器、父类、接口、父类的泛型、包、注解、异常等。。。。

1.获取属性：权限修饰符 数据类型 变量名

public class FiledTest {
       @Test    public void test(){
           Class clazz = Person.class;        //获取属性结构        //getFields():获取当前运行时类及其父类、接口中声明为public访问权限的属性        Field[] fields = clazz.getFields();        for(Field f : fields){
               System.out.println(f);        }        System.out.println();        //getDeclaredFields():获取当前运行时类中声明的所属性(包括公、默认、私，但不包含父类及其接口中声明的属性        Field[] declaredFields = clazz.getDeclaredFields();        for(Field f : declaredFields){
               System.out.println(f);        }    }    //权限修饰符  数据类型 变量名    @Test    public void test1(){
           Class clazz = Person.class;        //权限修饰符        Field[] declaredFields = clazz.getDeclaredFields();        for(Field f : declaredFields){
               //权限修饰符            int modifiers = f.getModifiers();            System.out.print(Modifier.toString(modifiers) + " ");            //数据类型            Class type = f.getType();            System.out.print(type.getName() + " ");            //变量名            String name = f.getName();            System.out.print(name);            System.out.println();        }    }}

2.获取方法：权限修饰符 返回值类型 方法名(参数类型1 形参名1,…) throws XxxException{}

public class MethodTest {
       @Test    public void test1(){
           Class clazz = Person.class;        //getMethods():获取当前运行时类及其所父类(包括Object)中声明为public权限的方法        Method[] methods = clazz.getMethods();        for(Method m : methods){
               System.out.println(m);        }        System.out.println();        //getDeclaredMethods():获取当前运行时类中声明的所方法。（不包含父类中声明的方法        Method[] declaredMethods = clazz.getDeclaredMethods();        for(Method m : declaredMethods){
               System.out.println(m);        }    }    /*    @Xxxx    权限修饰符  返回值类型  方法名(参数类型1 形参名1,...) throws XxxException{}     */    @Test    public void test2(){
           Class clazz = Person.class;        Method[] declaredMethods = clazz.getDeclaredMethods();        for(Method m : declaredMethods){
               //1.获取方法声明的注解            Annotation[] annotations = m.getAnnotations();            for (Annotation a : annotations){
                   System.out.println(a);            }            //2.权限修饰符            int modifiers = m.getModifiers();            System.out.print(Modifier.toString(modifiers) + " ");            //3.返回值类型            Class returnType = m.getReturnType();            System.out.print(returnType.getName() + " ");            //4.方法名            String name = m.getName();            System.out.print(name + "(");            //5.形参列表            Class[] parameterTypes = m.getParameterTypes();            if(parameterTypes.length > 0){
                   for (int i = 0; i < parameterTypes.length; i++) {
                       if(i == parameterTypes.length - 1){
                           System.out.print(parameterTypes[i].getName() +" " + "args_" + i);                        break;                    }                    System.out.print(parameterTypes[i].getName() + " " + "args_" + i + ",");                }            }            System.out.print(")" + " ");            //6.抛出的异常'            Class[] exceptionTypes = m.getExceptionTypes();            if(exceptionTypes.length > 0){
                   System.out.print("throws" + " ");                for (int i = 0; i < exceptionTypes.length; i++) {
                       if(i == exceptionTypes.length -1){
                           System.out.print(exceptionTypes[i].getName());                        break;                    }                    System.out.print(exceptionTypes[i].getName() + ",");                }            }            System.out.println();        }    }}

3. 获取构造器结构

public class OtherTest {
       /*    获取构造器结构     */    @Test    public void test1() {
           Class clazz = Person.class;        //getConstructors():获取当前运行时类(不包括父类的)中声明为public的构造器        Constructor[] constructors = clazz.getConstructors();        for (Constructor c : constructors) {
               System.out.println(c);        }        System.out.println();        //getDeclaredConstructors():获取当前运行时类中声明的所的构造器        Constructor[] declaredConstructors = clazz.getDeclaredConstructors();        for (Constructor c : declaredConstructors) {
               System.out.println(c);        }    }

4.获取运行时类的父类

/*  获取运行时类的父类   */    @Test    public void test2() {
           Class clazz = Person.class;        Class superclass = clazz.getSuperclass();        System.out.println(superclass);//class loey.Person.Creature    }

5. 获取运行时类的带泛型的父类

/*    获取运行时类的带泛型的父类     */    @Test    public void test3() {
           Class clazz = Person.class;        Type genericSuperclass = clazz.getGenericSuperclass();        System.out.println(genericSuperclass);//loey.Person.Creature
   
            /*        获取运行时类的带泛型的父类的泛型        代码：逻辑性代码  vs 功能性代码         */        ParameterizedType parameterizedType = (ParameterizedType) genericSuperclass;        //获取泛型类型        Type[] actualTypeArguments = parameterizedType.getActualTypeArguments();        //        System.out.println(actualTypeArguments[0].getTypeName());//        System.out.println(((Class)actualTypeArguments[0]).getName());        for (Type t : actualTypeArguments) {
               System.out.println(t.getTypeName());        }    }
   

6.获取运行时类实现的接口

/*   获取运行时类实现的接口    */    @Test    public void test4() {
            Class clazz = Person.class;        Class[] interfaces = clazz.getInterfaces();        for(Class i : interfaces){
               System.out.println(i);        }        System.out.println();        //获取运行时类的父类实现的接口        Class superclass = clazz.getSuperclass();        Class[] interfaces1 = superclass.getInterfaces();        for(Class c : interfaces1){
               System.out.println(c);        }    }

7. 获取运行时类所在的包

/*        获取运行时类所在的包     */    @Test    public void test5(){
           Class clazz = Person.class;        Package aPackage = clazz.getPackage();        System.out.println(aPackage);    }

8.获取运行时类声明的注解

/*        获取运行时类声明的注解     */    @Test    public void test6(){
           Class clazz = Person.class;        Annotation[] annotations = clazz.getAnnotations();        for(Annotation a : annotations){
               System.out.println(a);        }    }}

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