Java反射-操作Field、Method、Constructor Java反射-操作Field、Method、Con

1，Field、Method、Constructor中的反射数据

1）Field类

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2）Method类

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3）Constructor类

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4）The AccessibleObject class is the base class for Field, Method and
Constructor objects.

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2，打印所有成员变量、方法、构造器

public static void main(String[] args) { Field[] fields = String.class.getDeclaredFields(); for(Field field : fields){ field.setAccessible(true); System.out.println(Modifier.toString(field.getModifiers()) + " " + field.getType().getSimpleName() + " " + field.getName() + "; "); }System.out.println("----------------------------"); Method[] methods = String.class.getDeclaredMethods(); for(Method method : methods){ method.setAccessible(true); String temp = Modifier.toString(method.getModifiers()) + " " + method.getReturnType() + " " + method.getName() + "("; for(Class clazz : method.getParameterTypes()){ temp += clazz.getSimpleName() + ","; } temp = temp.substring(0, (temp.lastIndexOf(",") == -1)?temp.length():temp.lastIndexOf(",")); temp += ")"; System.out.println(temp); }System.out.println("----------------------------"); Constructor[] constructors = String.class.getDeclaredConstructors(); for(Constructor constructor : constructors){ constructor.setAccessible(true); String temp = Modifier.toString(constructor.getModifiers()) + " " + constructor.getName() + "("; for(Class clazz : constructor.getParameterTypes()){ temp += clazz.getSimpleName() + ", "; } temp = temp.substring(0, (temp.lastIndexOf(",") == -1)?temp.length():temp.lastIndexOf(",")); temp += ")"; System.out.println(temp); } }

3，Field、Method、Constructor上

【Java反射-操作Field、Method、Constructor】1）是否有指定注解(自定义注解的处理)
2）modifier判断

public static void main(String[] args) throws Exception { Method method = Class.class.getDeclaredMethod("newInstance", null); if(method.isAnnotationPresent(CallerSensitive.class)){ System.out.println(method.getDeclaringClass()); System.out.println(Modifier.isStatic(method.getModifiers())); System.out.println(Modifier.isPublic(method.getModifiers())); System.out.println(Modifier.isPrivate(method.getModifiers())); }Field field = Class.class.getDeclaredField("name"); if(!field.isAnnotationPresent(CallerSensitive.class)){ System.out.println(field.getName()); System.out.println(Modifier.isStatic(field.getModifiers())); System.out.println(Modifier.isPublic(field.getModifiers())); System.out.println(Modifier.isPrivate(field.getModifiers())); }Constructor constructor = Class.class.getDeclaredConstructor(ClassLoader.class); if(!constructor.isAnnotationPresent(CallerSensitive.class)){ System.out.println(constructor.getDeclaringClass()); System.out.println(Modifier.isStatic(constructor.getModifiers())); System.out.println(Modifier.isPublic(constructor.getModifiers())); System.out.println(Modifier.isPrivate(constructor.getModifiers())); } }