Thinking in Java is a book’s name, a good book. This afternoon, I did a hard work to find a method which can check that a char is a letter or not, but got no answer. I complained that Java is too hard to learn if I don’t know any class library and its method, everything I need to deal by myself, then MagicPig advise us to read the book Thinking in Java, said that it will be the best book to learn Java.

I spent nearly the hole day to type some simple code of the text book, and get many errors some seems strange, there may be a good experiences and wealth, because it can make me not to do the stupid thing again and again. But there is still a little problem need to fixed, which I can’t use Ant in Eclipse to compile a .jar file and to run the .jar file by double-click, there is always a error hint break out when I try to run the .jar file by double-click, I doubt there is something wrong in the build.xml file, but I don’t know how to correct it also I used Baidu and Google for a solution.