Start of the Java Arbor Day

I came back from work this evening to do something

1,liuyang has given a JDK installation package.

The installation steps and environment configuration are based on http://jingyan.baidu.com/article/6dad5075d1dc40a123e36ea3.html.

Eclipse is downloaded on the website.

2, when these are done, create project to create the class. I can't even write HelloWorld. So 39 gave me a code. I tried to run it again, with a lot of red forks.

The problem now is to name the same, I did not change, directly to the past.

And then I wrote a string code in the book and it was a lot of mistakes. Also shouted Liuyang Remote Assistance, the problem is now, one more. What a silly question.

Attached today code

Package Test1;public class String02 {private static String Geta () {return "a";} public static void Main (string[] args) {String A = "a"; final String C = "a"; the//final modifier enforces a constraint on String B = A + "b" from the definition; String d = c + "B"; String e = geta () + "B"; String compare = "AB"; System.out.println (b = = Compare);//falsesystem.out.println (d = = Compare);//truesystem.out.println (E = = Compare);// FalseSystem.out.println ("Hello World");}} Compare is a constant and b=a+ "B"; it is not a constant, although a is a local variable and a constant, but its reference does not impose a constraint,//Although the code does not change, but when it is run, anything happens, especially in "bytecode enhancement" Technology, changes occur when the code is cut into place.

Package Test1;public class Test02 {public static void main (string[] args) {String a = "a"; String B = A + "B"; String C = "AB"; String d =new string (b); System.out.println (b==c);//falsesystem.out.println (C==d);//falsesystem.out.println (C==d.intern ());// TrueSystem.out.println (b.intern () = = D.intern ());//true}}//use intern to guarantee global uniqueness of strings of the same value

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Start of the Java Arbor Day