获取类的元数据信息

package classhandle;
import ng.reflect.Field;
import ng.reflect.Modifier;
import java.sql.Timestamp;
import java.util.Calendar;
public class GetMetaDataInformationOfClass {
/**
* @param args
*/
public static void main(String[] args) {
// TODO Auto-generated method stub
Calendar birthday = Calendar.getInstance();
birthday.set(1988, 1, 11, 0, 1, 0);
Student stu = new Student("0002", "人参", true, new Timestamp(
birthday.getTimeInMillis()), 1.80);
// System.out.println(birthday.getTimeInMillis());
ClassInfo classInfo = new ClassInfo();
System.out.println(classInfo.getClassInfo(stu));
}
}
class ClassInfo {
public String getClassInfo(Object obj) {
StringBuffer result = new StringBuffer();
// 得到参数变量的Class引用变量
Class cls = obj.getClass();
// System.out.println(cls);
// 得到参数类变量的信息
Field[] fields = cls.getDeclaredFields();
// 得到参数类变量的完整类名（含有包的名称）
String fullName = cls.getName();
// System.out.println(fullName);
// 得到去除包名称的类名
String className = fullName.substring(fullName.indexOf(".") + 1);
// System.out.println(className);
// 如果有包的定义，可以得到包的名称
int packagePosition = stIndexOf('.');
// System.out.println(packagePosition);
String packageName = null;
if (packagePosition < 0)
packageName = "";
else
packageName = fullName.substring(0,
stIndexOf('.'));
// System.out.println(packageName);
// 输出包名和类名
result.append("包的名称：" + packageName + "\n");
result.append("类的名称：" + className + "\n");
for (Field field : fields) {
// 允许访问私有成员
field.setAccessible(true);
try {
// 输出私有属性信息
if (field.getModifiers() == Modifier.PRIVATE) {
result.append("私有属性" + field.getName() + "值为"
+ field.get(obj) + "\n");
}
// 输出受保护属性信息
if (field.getModifiers() == Modifier.PROTECTED) {
result.append("受保护属性" + field.getName() + "值为"
+ field.get(obj) + "\n");
}
} catch (IllegalArgumentException e) {
// TODO Auto-generated catch block
e.printStackTrace();
} catch (IllegalAccessException e) {
// TODO Auto-generated catch block
e.printStackTrace();
}
}
return result.toString();
}
}
class Student {
private String number = null;
private String name = null;
private boolean sex = false;
private Timestamp birthday = null;
private double height = 0;
public String getNumber() {
return number;
}
public void setNumber(String number) { this.number = number;
}
public String getName() {
return name;
}
public void setName(String name) {
= name;
}
public boolean isSex() {
return sex;
}
public void setSex(boolean sex) {
this.sex = sex;
}
public Timestamp getBirthday() {
return birthday;
}
public void setBirthday(Timestamp birthday) {
this.birthday = birthday;
}
public double getHeight() {
return height;
}
public void setHeight(double height) {
this.height = height;
}
public Student() {
}
public Student(String number, String name, boolean sex, Timestamp birthday,
double height) {
setNumber(number);
setName(name);
setSex(sex);
setBirthday(birthday);
setHeight(height);
}
public String toString() {
return"学号:" + number + "\n姓名:" + name + "\n是否男性：" + sex + "\n生日："
+ birthday + "\n身高：" + height;
}
}。