从XML文件配置JNDI InitialContext

Question

I'd like to define JNDI lookups in my app's own XML config file (somewhat similar to Tomcat's context.xml ), and then reference them in my app. Then, under the hood, the app uses JNDI to look the objects up with the information stored in the XML file.

For instance, given the following snippet from my app's XML config file:

<app>
    <!-- lots of stuff -->

    <dataSource name="jdbc/myDB"
        maxActive="50" maxIdle="30" maxWait="10000"
        username="mysqluser" password="mysqlpassword" 
        driverClassName="com.mysql.jdbc.Driver"
        url="jdbc:mysql://localhost:3306/myDB"/>

    <!-- lots of stuff -->
</app>

Then, in my app:

public class DataSourceProvider {
    public DataSource lookupDataSource(String name) {
        DataSource dataSource = null;
        try {
            Context context = new InitialContext();
            dataSource = (DataSource) context.lookup("Database");
        } catch (NamingException e) {
            // Handle...
        }

        return dataSource;
    }
}

DataSourceProvider dsp = new DataSourceProvider();
DataSource myDB = dsp.lookupDataSource("myDB");

How do I link these two concepts together? Say the <dataSource/> XML element gets read into a DataSourceVO object. How do I configure the InitialContext instance from the DataSourceVO instance, such that we can perform the JNDI lookup? Thanks in advance!

Update : I found this example:

try{   
    Hashtable env = new Hashtable();   
    env.put(Context.INITIAL_CONTEXT_FACTORY,   
            "com.sun.jndi.ldap.LdapCtxFactory");   
    env.put(Context.SECURITY_AUTHENTICATION, "simple");

    String securityPrincipal = domain + "\\" + user;

    env.put(Context.SECURITY_PRINCIPAL, securityPrincipal);   
    env.put(Context.SECURITY_CREDENTIALS, password);   
    env.put(Context.PROVIDER_URL, "ldap://" + domainController);   

    ctx = new InitialDirContext(env);   
} catch (AuthenticationException ex) { 
    ex.printStackTrace();
} catch(NamingException nex){   
    nex.printStackTrace();   
}

Is this what I'm looking for? That way, I could read my XML into a Hashtable (or something similar) and then create the InitialContext from that table? Is that all there is to it?!?

Answer 1

Try Spring http://static.springsource.org/spring/docs/3.2.x/spring-framework-reference/html/jdbc.html#jdbc-connections , see 14.3.1 DataSource

<bean id="dataSource" class="org.springframework.jdbc.datasource.DriverManagerDataSource">
    <property name="driverClassName" value="${jdbc.driverClassName}"/>
    <property name="url" value="${jdbc.url}"/>
    <property name="username" value="${jdbc.username}"/>
    <property name="password" value="${jdbc.password}"/>
</bean>

<context:property-placeholder location="jdbc.properties"/>

If Spring is not an option then you can configure the data source using Properties

Properties props = new Properties();

... load from properties file or XML 

BasicDataSource ds = new BasicDataSource();
for(Entry e : props.entrySet()) {
    ds.addConnectionProperty((String)e.getKey(), (String)e.getValue());
}