Other people's point of view: How to master Java

Often see some people say that Master Java, but let them use Java to do a real project may be difficult, here, the author based on their own a little understanding of some of the standard to master Java, of course, for beginners, also can provide a need to learn what content reference. In addition, this standard is limited to the J2SE part, the contents of the Java EE section have time to say otherwise. 1, the grammar: must be more familiar with, in writing code when the IDE editor to a row of the error should be able to according to the error information to know what kind of syntax errors and know any corrections. 2, command: Must be familiar with the JDK with some of the common commands and common options, commands need to be familiar with at least: Appletviewer, Htmlconverter, jar, Java, Javac, Javadoc, JAVAP, JAVAW, Native2ascii , Serialver, if you haven't used all of these commands, then you don't really know much about Java. 3. Tools: Must be proficient at least one IDE development tool, such as Eclipse, Netbeans, JBuilder, JDeveloper, Idea, JCreator, or workshop, including engineering management, common options settings, Plug-in installation configuration and debugging. 4, Api:java's core API is very large, but there are some content I think must be familiar with, otherwise it is impossible to skillfully use Java, including:    1, Java.lang under 80% of the class functions of flexible use.     2, the flexible use of more than 80% of the classes under the Java.util package, especially the collection class system, regular expressions, zip, and time, random numbers, attributes, resources, and timer.     3), the use of more than 60% of the classes under the Java.io package, to understand the IO system based on the pipeline model design ideas and common IO class characteristics and use of occasions.     4), under the Java.math package of 100% of the content.     5), java.net package of more than 60% of the content, the functions of each class are more familiar.     6), under the java.text package of more than 60% of the content, especially the various formatting classes.     7), skilled use of JDBC.     8), java.security package under more than 40% of the content, if there is no contact with security can not master Java.     9, the basic content of AWT, including a variety of component events, listeners, Layout manager, common components, printing.     10, the basic content of swing, similar to the requirements of AWT.     11, XML processing, familiarity with the pros and cons of Sax, Dom, and jdom and the ability to use one of these to complete XML parsing and content processing. 5. Testing: Must be familiar with the use of JUnit to write test case completion code of the automated test. 6, Management: Must be familiar with ant to complete engineering management of common tasks, such as Project compilation, build Javadoc, build jars, version control, automated testing. 7, error: should be able to according to the exception information more rapid positioning of the cause and approximate location of the problem. 8, thought: Must master the main requirements of OOP, so that the use of Java development system can be a real Java system. 9, Specifications: The code must be written to conform to the popular coding norms, such as the first letter of the class name, the members and methods of the first letter lowercase, method name is generally a verb, package name all lowercase, etc., so that the program readability is better.