如何在Eclipse的web.xml中添加上下文参数？

Question

I am using Eclipse Mars(Version: Mars Release (4.5.0)).

Basically i am developing a small Web Application that has login form and a link that goes to registering new user.

Here i am supposed to interact with my database couple of times for verifying login details and for registering new user details.

So i want to add database details(like driver,url,username,password) in context parameters in web.xml to avoid HardCoding ? How am i supposed to do that?Thank you.

Answer 1

web.xml is not elegant way to keep that kind of data as login/password/driver etc.

There are few approaches that you could implement for that kind data.

JNDI approach
Configuration depends on what web container/server are you using right now. As you mentioned this is simple web application propably you are using Tomcat so here please refer to this for more details and example: Tomcat and JNDI

Configuration stored in property file approach
You need to store these data in your property file called for example db.properties

#Properties structure
db.url=your_db_url
db.driver=your_db_driver
db.login=your_db_login
db.password=your_db_password

This file should be placed in your src/resources catalog. So after making webapp package it should be in WEB-INF/classes path of your web application

db.properties should be load somehow in your code for example:

Properties prop = new Properties();
InputStream input = null;

try {

    input = new FileInputStream("db.properties");

    // load a properties file
    prop.load(input);

    // get the property value and print it out
    String url = prop.getProperty("db.url");
    String driver = prop.getProperty("db.driver");
    String login = prop.getProperty("db.login");
    String password = prop.getProperty("db.password");

    //Your code to connect to db
} catch (IOException ex) {
    ex.printStackTrace();
} finally {
    if (input != null) {
        try {
            input.close();
        } catch (IOException e) {
            e.printStackTrace();
        }
    }
}

More approaches can be defined but everything depends on what framework are you actualy working.

Handle this maybe like a guideline not step-by-step. It is up to you which way do you use.