什么是MyClass.class？

Z时代
2024-01-10
分类：问答

以下是MainClass.java中列出的代码。

public class MainClass {
    public static void main(String[] args) {
        System.out.println("main started...");
        Class c = MyClass.class ;
                        //this class variable seems to be public static.
                        //But, as it is clearly visible in the MyClass,
                        //no reference variable is declared.
                        //My problem is that from where this class variable
                        //came from.
                        //i also check out the Object.java file, but it also don't
                        //have any public static class variable of Class class
                        //like there is
                        //out (instance of PrintStream class) in System class.
                        //Hope all u mindoverflow guys help me to sort out
                        //this probz.
        try {
            Class.forName( c.getName() ) ;
            System.out.println("classloader of MyClass : " + MyClass.class.getClassLoader());
            System.out.println("classloader of MyClass : " + String.class.getClassLoader());
        } catch (ClassNotFoundException e) {
            e.printStackTrace();
        }
        System.out.println("main ended...");
    }
}
class MyClass{
    static{
        System.out.println("static block of MyClass class.");
    }
}

thnx coobird …我发现这篇文章很有用。:)

但是，关于litereals，我的知识仅限于：

int i = 5 ;  //here 5 is an integer literal
float f = 5.6f ;  //here 5.6f is a float literal

我知道的唯一非原始的litereal

String str = "java" ;   //"java" is a String litereal

和类字面量，你和乔恩·斯基特（Jon Skeet）对我很清楚。

同意…因此，根据讨论，总字面量归类为：

原始文字

字符串文字

类文字

空值

还有更多的文字（使列表更长一些）

public class MainClass {
    public static void main(String[] args) {
        System.out.println("main started...");
        Class c = MyClass.class ;
        try {
            Class.forName( c.getName() ) ;
            System.out.println("classloader of MyClass : " + MyClass.class.getClassLoader());
            System.out.println("classloader of MyClass : " + String.class.getClassLoader());
        } catch (ClassNotFoundException e) {
            e.printStackTrace();
        }
        System.out.println("main ended...");
    }
}

import java.io.PrintStream;
public class MainClass
{
    public MainClass()
    {
    }
    public static void main(String args[])
    {
        System.out.println("main started...");
        Class c = MyClass;
        try
        {
            Class.forName(c.getName());
            System.out.println((new StringBuilder("classloader of MyClass : ")).append(MyClass.getClassLoader()).toString());
            System.out.println((new StringBuilder("classloader of MyClass : ")).append(java/lang/String.getClassLoader()).toString());
        }
        catch(ClassNotFoundException e)
        {
            e.printStackTrace();
        }
        System.out.println("main ended...");
    }
    static Class class$0;
    static Class class$1;
}