A simple point about a servlet is actually a middle-tier interface that handles client requests on a Web server.
Second, about thread 1, general integration runnable or THREAD2, thread synchronization using synchronized
Third, about the exception Java provides many exception classes, specific access to relevant information, here to pay attention to the following points 1, try block is best for the exception module, do not blind Chunk 2, try to use finally to dispose of resources 3, exception handling and description of the problem needs to be targeted 4, as far as possible to use specific exception class, Catch real anomalies, remember the general
Custom exception class General inheritance exception
Iv. There are two types of data streams for Iojava: byte stream and character stream
Byte stream: Typically a binary reference function FileInputStream or FileOutputStream bufferinputstream or Bufferoutputstream
Character stream: Generally a reference function exists in the form of a string filereader or FileWriter BufferedReader or BufferedWriter
Five, about the database is currently more popular is the use of JDBC as a database-driven interface similar to Microsoft's ADO
VI. Tools for a unit test of JUnit, somewhat similar to Python's testcase
Seven, about the Log4jjava log module, specific information can refer to the official documents, mainly configuration issues such as log level, log storage format, log formats, as well as the type of log (by size or time)
Viii. about spring an MVC-based web framework 1, the core idea is the dependency injection and can be configured to change the business logic, instead of changing the core code
2. Core Block Diagram
Explanation: 1, Viewresolver: Find the corresponding implementation view 2 by the view name returned in the Modelandview, view: Populating the model data into the view layer is important two configurations: Web. XML: The configuration responsible for service startup, The spring distribution core is dispatcherservlet so there is a need to initialize the Disaptcherservlet-related configuration file loading.
Servlet.xml: This file is mainly used by Dispatcherservlet, which defines the mapping of views, controllers and so on, and the configuration dependent on injection, which is very important
Ix. about struct
An MVC-based web Framework 1, Core framework
1. Actionservlet Inheritance and HttpServlet parsing client requests, populating Actionform (for example, some parameters)
2, through actionmapping the request page distribution to the corresponding action, action by processing the specific business data, the results are imported Actionform
3, actionmapping based on the return results forward jsp,jsp through the taglibs from the actionform to get data fill
4. Return to the front end via HttpResponse.
Some concepts of Java are organized
