Java反射通用类 获取所有成员变量 构造方法 成员方法

import java.lang.reflect.Constructor;
import java.lang.reflect.Field;
import java.lang.reflect.Method;
import java.lang.reflect.Modifier;

public class ReflectUtil {

public static void main(String[] args) {
try {
String classNameString = "java.lang.Math";
Class c = Class.forName(classNameString);

reflectDeclaredFields(c);
System.out.println("\n");
reflectDeclaredConstructors(c);
System.out.println("\n");
reflectDeclaredMethods(c);

reflectFields(c);
System.out.println("\n");
reflectConstructors(c);
System.out.println("\n");
reflectMethods(c);

} catch (Exception e) {
e.printStackTrace();
}
}

/**
* 反射所有变量
*
* @param c
*/
public static void reflectDeclaredFields(Class c) {
try {
Field[] fields = c.getDeclaredFields();
System.out.println("this class has " + fields.length + " field");
for (Field field : fields) {
System.out.println(Modifier.toString(field.getModifiers()) + " " + field.getType().getSimpleName() + " "
+ field.getName());
// System.out.println(field);
}
} catch (Exception e) {
e.printStackTrace();
}
}

public static void reflectFields(Class c) {
try {
Field[] fields = c.getFields();
System.out.println("this class has " + fields.length + " field");
for (Field field : fields) {
System.out.println(Modifier.toString(field.getModifiers()) + " " + field.getType().getSimpleName() + " "
+ field.getName());
// System.out.println(field);
}
} catch (Exception e) {
e.printStackTrace();
}
}

/**
* 反射所有构造方法
*
* @param c
*/
public static void reflectDeclaredConstructors(Class c) {
try {
Constructor[] constructors = c.getDeclaredConstructors();
System.out.println("this class has " + constructors.length + " constructor");
for (Constructor constructor : constructors) {
StringBuilder sb = new StringBuilder(
Modifier.toString(constructor.getModifiers()) + " " + constructor.getName() + "(");
Class[] types = constructor.getParameterTypes();
if (types.length > 0) {
for (Class type : types) {
sb.append(type.getSimpleName() + ",");
}
sb.deleteCharAt(sb.length() - 1);
}
sb.append(")");
System.out.println(sb);
// System.out.println(constructor);
}
} catch (Exception e) {
e.printStackTrace();
}
}

public static void reflectConstructors(Class c) {
try {
Constructor[] constructors = c.getConstructors();
System.out.println("this class has " + constructors.length + " constructor");
for (Constructor constructor : constructors) {
StringBuilder sb = new StringBuilder(
Modifier.toString(constructor.getModifiers()) + " " + constructor.getName() + "(");
Class[] types = constructor.getParameterTypes();
if (types.length > 0) {
for (Class type : types) {
sb.append(type.getSimpleName() + ",");
}
sb.deleteCharAt(sb.length() - 1);
}
sb.append(")");
System.out.println(sb);
// System.out.println(constructor);
}
} catch (Exception e) {
e.printStackTrace();
}
}

/**
* 反射所有成员方法
*
* @param c
*/
public static void reflectDeclaredMethods(Class c) {
try {
Method[] methods = c.getDeclaredMethods();
System.out.println("this class has " + methods.length + " method");
for (Method method : methods) {
StringBuilder sb = new StringBuilder(Modifier.toString(method.getModifiers()) + " "
+ method.getReturnType().getSimpleName() + " " + method.getName() + "(");
Class[] types = method.getParameterTypes();
if (types.length > 0) {
for (Class type : types) {
sb.append(type.getSimpleName() + ",");
}
sb.deleteCharAt(sb.length() - 1);
}
sb.append(")");
System.out.println(sb);
// System.out.println(method);
}
} catch (Exception e) {
e.printStackTrace();
}
}

public static void reflectMethods(Class c) {
try {
Method[] methods = c.getDeclaredMethods();
System.out.println("this class has " + methods.length + " method");
for (Method method : methods) {
StringBuilder sb = new StringBuilder(Modifier.toString(method.getModifiers()) + " "
+ method.getReturnType().getSimpleName() + " " + method.getName() + "(");
Class[] types = method.getParameterTypes();
if (types.length > 0) {
for (Class type : types) {
sb.append(type.getSimpleName() + ",");
}
sb.deleteCharAt(sb.length() - 1);
}
sb.append(")");
System.out.println(sb);
// System.out.println(method);
}
} catch (Exception e) {
e.printStackTrace();
}

}

}