Class.forName的使用

Class.forName的使用

Class.forName返回一个类，使用此方法可以获取类

首先，创建一个Student类

/***
 * This Class is for Student bean
 * @author Young
 *
 */
public class Student {

    private int stud_Id;
    private String stud_Name;
    private String sex;
    private String birthday;
    private String score;

    public int getStud_Id() {
        return stud_Id;
    }

    public void setStud_Id(int stud_Id) {
        this.stud_Id = stud_Id;
    }

    public String getStud_Name() {
        return stud_Name;
    }

    public void setStud_Name(String stud_Name) {
        this.stud_Name = stud_Name;
    }

    public String getSex() {
        return sex;
    }

    public void setSex(String sex) {
        this.sex = sex;
    }

    public String getBirthday() {
        return birthday;
    }

    public void setBirthday(String birthday) {
        this.birthday = birthday;
    }

    public String getScore() {
        return score;
    }

    public void setScore(String score) {
        this.score = score;
    }

    /**
     * This method is a constructor
     * 
     * @author Young
     * @param id
     * @param name
     * @param sex
     * @param birthday
     * @param score
     */
    public Student(int id, String name, String sex, String birthday,
            String score) {

        this.stud_Id = id;
        this.stud_Name = name;
        this.sex = sex;
        this.birthday = birthday;
        this.score = score;
    }
    
    public Student() {

        this.stud_Id = 1000200;
        this.stud_Name = "Test";
        this.sex = "Male";
        this.birthday = "2015/01/28";
        this.score ="3.3";
    }
}

然后使用该类

Class<?> c = Class.forName(Student.class.getCanonicalName());
        Object obj=c.newInstance();
        for(Method m:c.getMethods())
        {
            System.out.println(m.getName());
            if(m.getName().equals("getId"))
            {
                System.out.println(m.invoke(obj));
            }

使用invoke运行该类的方法

使用getInstance方法获取一个对象

获取不带参数的对象，如果遇到带参数的对象该怎么获取？

        Class<?> c = Class.forName(Student.class.getCanonicalName());
        Constructor<?> constructor = c.getConstructor(Integer.TYPE,
                String.class, String.class, String.class, String.class);
        Object obj = constructor.newInstance(1, "Test", "Male", "2015-07-09",
                "80");
        for (Method m : c.getMethods()) {
            System.out.println(m.getName());
            if (m.getName().equals("getSex")) {
                System.out.println(m.invoke(obj));
            }
        }

使用Constructor ，可以设置参数