java反思reflect 分析Object物

直接看它的一个例子

</pre><pre name="code" class="java">package reflect;

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

class Behavior {
private long distance;
private long amount;

public long getDistance() {
return distance;
}

public void setDistance(long distance) {
this.distance = distance;
}

public long getAmount() {
return amount;
}

public void setAmount(long amount) {
this.amount = amount;
}

public String walk() {
return "走了" + distance + "公里";
}

public String eat() {
return "吃了" + amount + "碗饭";
}

}

class Person extends Behavior {
private String username;
private int age;
static char sex;
protected final double high = 0;
public String[] hobby;
public Behavior be;

public String getUsername() {
return username;
}

public void setUsername(String username) {
this.username = username;
}

public int getAge() {
return age;
}

public void setAge(int age) {
this.age = age;
}

public char getSex() {
return sex;
}

public static void setSex(char sex) {
Person.sex = sex;
}

public double getHigh() {
return high;
}

public String[] getHobby() {
return hobby;
}

public void setHobby(String[] hobby) {
this.hobby = hobby;
}

public Behavior getBe() {
return be;
}

public void setBe(Behavior be) {
this.be = be;
}

public Person() {

}

public Person(String username, int age, String[] hobby, Behavior be) {
super();
this.username = username;
this.age = age;
this.hobby = hobby;
this.be = be;
}

public String fun2(int a, int b, int c, String d, double e, float f, char g) {
return a + b + c + d + e + f + g;
}

}

public class ObjectAnalyzer {

public void printFields(Field[] fields) {
for (int i = 0; i < fields.length; i++) {
Field f = fields[i];
int m = f.getModifiers();
String name = f.getName();
Class<?

> clazz = f.getType();
System.out.println(Modifier.toString(m) + " " + clazz.getName()
+ " " + name);
}
}

public void printConstructor(Constructor<?>[] c) {
for (int i = 0; i < c.length; i++) {
Constructor<?

> con = c[i];
String name = con.getName();
int m = con.getModifiers();
Class<?>[] clazz = con.getParameterTypes();
System.out.print(Modifier.toString(m) + " " + name + "(");
for (int j = 0; j < clazz.length; j++) {
System.out.print(clazz[j].getName() + " ");
}
System.out.println(")");
}
}

public void printMethod(Method[] methods) {
for (int i = 0; i < methods.length; i++) {
Method m = methods[i];
int modi = m.getModifiers();
String name = m.getName();
Class<?> returnType = m.getReturnType();
Class<?>[] paramType = m.getParameterTypes();
System.out.print(Modifier.toString(modi) + " "
+ returnType.getName() + " " + name + "(");
for (int j = 0; j < paramType.length; j++) {
System.out.print(paramType[j].getName() + " ");
}
System.out.println(")");
}
}

public void analyzer(Object obj) {
Class<?> clazz = obj.getClass();
Field[] fields = clazz.getDeclaredFields();
Constructor<?>[] c = clazz.getDeclaredConstructors();
Method[] method = clazz.getDeclaredMethods();
//Method[] method = clazz.getMethods();
System.out.println("=====属性变量的分析=====");
System.out.println("Fields长度:" + fields.length + " 变量例如以下");
printFields(fields);
System.out.println("=====构造方法分析=====");
printConstructor(c);
System.out.println("=====方法分析=====");
printMethod(method);

}

public static void main(String[] args) {
// TODO Auto-generated method stub
Behavior be = new Behavior();
Person p = new Person("chiwei", 26, new String[] { "1", "2" }, be);
new ObjectAnalyzer().analyzer(p);
}

}

执行结果例如以下：

=====属性变量的分析=====

Fields长度:6 变量例如以下

private java.lang.String username

private int age

static char sex

protected final double high

public [Ljava.lang.String; hobby

public reflect.Behavior be

=====构造方法分析=====

public reflect.Person()

public reflect.Person(java.lang.String int [Ljava.lang.String; reflect.Behavior )

=====方法分析=====

public void setUsername(java.lang.String )

public int getAge()

public void setAge(int )

public char getSex()

public static void setSex(char )

public double getHigh()

public [Ljava.lang.String; getHobby()

public void setHobby([Ljava.lang.String; )

public reflect.Behavior getBe()

public void setBe(reflect.Behavior )

public java.lang.String fun2(int int int java.lang.String double float char )

public java.lang.String getUsername()