Original: Java foundation, parameter configuration, precautions! JDK1.5 + JSP + MYSQL + TOMCAT configuration

Java has always had its best benefits to choose it, but these casually overlooks or visit the answer on the Internet. In this article, the author writes some of the body of Java to learn Java, and the scholars are given a reference.

I am studying in the process of learning Java to learn from the following aspects:

1. Always remind yourself Java is an OOP language tool, not just coding, only in this way will grasp and use Java.

2. In the process of learning, it is best to understand the underlying mechanism of Java instead of staying in the surface, not the example of the copy of the book. It should be noted that even if there is a simple example, there must be patience, debug, and change.

3. Be sure to do it during the process of learning, write code, not to hold a book to see it. Many things and experiences must do their own to really belong to themselves, it is best to participate in some actual projects.

4. After learning a certain stage, what you have begun to do what you have learned. At this time, you should start learning some more, more complicated knowledge, such as the construction of the J2EE platform, EJB development, etc. For this part, I suggest that it is best to find a thin book to understand a matter, there is a general understanding in my heart, and a preliminary master of more technical terms. I think this stage look at "J2EE technology practice" is very good, it allows you to understand the various techniques and frames included in J2EE, while providing a lot of practical examples to deepen the overall understanding of J2EE.

Learning Java's interest and determination has played a key role. After having the above foundation, I started learning Java step by step.

Java Environment Building (Java Environment -Jsp-MySQL-Tomcat)

To run the Java program, you must install JDK. JDK is the core of the entire Java, including Java compiler, JVM, a large number of Java tools, and Java foundation APIs.

The JDK1.5 version can be downloaded from http://java.sun.com/j2se/1.5.0/download.jsp.

Unzip installation. Then, the environment is set. JDK1.5 download URL http://192.18.97.238/ECom/EComTicketServlet/BEGINB0896C8AB4D1F89812458DB1E451448D/-2147483648/651374223/1/531770/531614/651374223/2ts /westCoastFSEND/jdk-1.5.0-oth-JPR/jdk-1.5. 0-other-jpr: 1 / jdk-1_5_0-windows-i586.exe

http://java.sun.com/j2se/1.5.0/download.jsp

JCREATOR Pro 2.5 (with registration) http://www.java-cn.net/javatools/tools/jcpro250.zip

JDK1.5 JCREATOR Pro 2.5 Beginner's best compiler.

1, JDK's basic configuration:

Win2000, XP right-click "My Computer", select "Properties", select "Advanced", set "Environment Variable" Path Set to: C: / Program Files / Java / JDK1.5.0 (JDK Path) / bin;

Set java_home as: c: / program files / java / jdk1.5.0; // jdk path

ClassPath = C: / Program Files / Java / JDK1.5.0 (JDK Actual Path) / lib; (If you already have PATH and ClassPath, please do not delete the original value, add it directly to the back.)

Win98: Win9X, you need to modify the PATH and ClassPath variables of the autoexec.bat file under the root of the system:

SET PATH =% PATH%; C: / JDK 1.5 / bin; set classpath = .; c: / jdk 1.5 / lib; Re-executing autoexec.bat after the parking is described in the JDK's important commands:

◆ Java execution tool is a command to start JVM (virtual machine) and execute the class (Byte code) file;

◆ Javac compiler, generates a .class file by .class file;

◆ JAR JAVA compressed package tool;

◆ Javadoc document generator.

Finally, JDK Documentation, this is the JDK online help document, is the most useful and most important learning reference document, should look more.

2, Tomcat configuration:

(1) Set an environment variable: tomcat_home = f: / tomcatcatalina_home = f: / tomcatjava_home = C: / program files (the installation path, here is the default path) /Java/JDK1.5.0; Set ClassPath = f: / Tomcat / lib If you want to boot Tomcat with a command line, set PATH = "f: / tomcat"

(2) Enter http:// localhost: 8080 or http://127.080 or http://127.080 or http://127.0.0.0.1:8080 If you can see Tomcat Version 4.0, Tomcat is successful.

(3) Tomcat's configuration files are in its installation path / conf directory, the primary configuration file is Server.xml: Change the server listening port: Find , Vaule property value It is the port number and can be changed.

Add Virtual Path (service): user < Value> SA password driverclassname org.hsql.jdbcdriver drivername jdbc: hypersonicsql: Database

DocBase = "f: / myexample" debug = "0" RELOADABLE = "true"> The above example adds a service: Path indicates the URL path of the service, and DOCBASE represents the path to the hard disk. Debug indicates whether it is allowed to debug, and the reloadable indicates whether the servlet is automatically reloaded. Use mysql database: After downloading MySQL JDBC driver, put mm.mysql-2.0.4-bin.jar (some version is mysql-connector-java-3.0.9-stable-bin.jar) under Tomcat installation path Lib Directory. The JSP program of the test is as follows:

<% @ page contenttype = "text / html; charset = GB2312"%> <% // declaration java.sql.connection sqlconn; // database connection object java.sql.Statement SQLSTMT; // statement object java.sql.resultset SQLRST; / / Results

// Register the JDBC driver class.Forname ("org.gjt.mm.mysql.driver"). NewInstance ();

// Connect the database SQLCONN = java.sql.driverManager.getConnection ("JDBC: MySQL: // LocalHost / MySQL", "root", "root");

// Create a statement object SQLSTMT = SQLCONN.CREATESTATEMENT (java.sql.resultSet.Type_scroll_insensitive, java.sql.resultset.concur_read_only);

// Execute SQL statement SQLRST = SQLSTMT.ExecuteQuery ("SELECT * from user");%>