Learn JAVA notes ()

Notes, because the school a JAVA class, put me in touch with JAVA.
And then went to the online search GOOGLE for the JAVA, get a lot of information.
Go in and have a look, get confused, What Is API, what is an object-oriented ............ (Hey, hey, I what basis did not, is it very reckless .)
Immediately materials turned out to see, to skycn under a JDK. Installation-environment-run of the Great "Hello World ".
Installation is simple, configuration, it gives me a headache, or GOOGLE to find information, it is this:
The system variables-> New-> variable name: JAVA_HOME variable values: C: \ j2sdk1.4.1
The system variables-> New-> variable name: CLASSPATH variable value :.; % JAVA_HOME % \ Lib
The system variables-> edit-> variable name: PATH variable values at the front of the plus: % JAVA_HOME % \ bin;
Oh, OK.
In the run-type CMD, and then use javac and Java. Success, no error. And then edit the run HELLOWORLD.
Online around first, to understand the class and object of the concept. In an article, see this sentence: object transfer method, the method of attributes. I know. You can't directly to the class, can only through the Class A shi lie (objects) call the class method to change the properties of the object.
Because there is no the basis of language, so as they article say plastic data and the like, don't know, don't laugh at me. Fortunately, we book are introduced, and read a book. Although everyone said, teaching material is used to deal with the education system in China, and, but there are some basic things to look at this. Although I can't fully understand the object-oriented programming.
The teacher said, learning JAVA the key is to understand the object-oriented programming. Put him on the key. The teacher also introduced (tinking in Java) is very good, but it is in English, even my English is poor, have English lessons.
I was still young, I want to take advantage of the opportunity.