URL is not hierarchical ...
String b = "abcd " String a = "a " String c = "bcd " String d=a+c system.out.println (dashed constants) false Why false should be true according to the principle that there is only one copy of the java string constant. what does the memory d...
the java interface should not be instantiated, so why make the program work properly in the following form? (the screenshot on the ebook, the program actually clicked, but I don t know why) ...
java rookie, read java Core Technology introduction Graphics2D class is a subclass of Graphics, in which there is a code public void paintComponent (Graphics g) { Graphics2D g2 = (Graphics2D) g ...... } will there be no error in the downward transitio...
objects are transmitted in binary mode on the network. so for serialization, different serialization, the transferred object should be a binary stream. then why json and xml are also described as serialization. It is not very clear that both of them ha...
< H2 > NewFile.java < H2 > private File configurationFile; public NewFile(File file){ this.configurationFile = file; } public void newFile() throws IOException{ if (!configurationFile.exists()) configurationFile.createNewFile(); ...
the first code can be locked successfully public class Main { public static void main(String[] args){ LockThread lock1 = new LockThread(true); LockThread lock2 = new LockThread(false); Thread thread1 = new Thread(lock1); Thread th...
but what if I call system.in.read () again after closing it? does its instance BufferedInputStream shut down automatically immediately after it is used up? Or are you waiting for recycling? ...
Student.java private int age; private String name; public Student(int age, String name){ this.name = name; this.age = age; } public void setAge(int age) { this.age = age; } public String getName() { return name; } public void setNam...
the problem is as follows ajax :header : Home components <template> <div class="home"> <header class="home-header"> header < header> <div class="scroll...
the code is here, line 64 https: github.com ant-design. I don t quite understand why. I need to add {list} after list, and I haven t seen a similar syntax in es6 . is it any good for them to write like this? how to understand it? thank you ...
problem description I found that axios sends an option request before each request, verifying methods that can be cross-domain. This implementation may be more standard, but there is no such additional request when using jquery before. when I think ...
just came into contact with the dva framework. I judged in subscriptions that when the current route is entered, it should not be called only once. `subscriptions: { getPageData({ dispatch, history }) { return history.listen(({ pathname, query }) =&g...
problem description cannot find a method to dynamically obtain the width and height of the original picture the environmental background of the problems and what methods you have tried if the original picture is small, img will follow the size of ...