Three forms of velocity template loading

This article explains the three ways of loading velocity templates

1: Velocity default loading method (file loading) (the following is the directory structure for file loading)

 

 

1. Directly read the resource file method

 

public class VelocityTemplate {
    public static String getVelocityTemplate(String basePath) throws Exception {
        String sysRoot = VelocityTemplate.class.getResource("").getPath();
        Properties properties = new Properties();
        / / Set the velocity resource loading method to file
        properties.setProperty("resource.loader", "file");
        //Set the processing class when the velocity resource loading method is file
        properties.setProperty("file.resource.loader.class","org.apache.velocity.runtime.resource.loader.FileResourceLoader");
        properties.put("input.encoding", "UTF-8");
        properties.put("output.encoding", "UTF-8");
        //Instantiate a VelocityEngine object
        VelocityEngine velocityEngine = new VelocityEngine(properties);
        //Instantiate a VelocityContext
        VelocityContext velocityContext = new VelocityContext();
        //Put key values ​​into VelocityContext
        context.put("username", "张三");
        context.put("password", "123456789");
        context.put("age", "20");
        //Instantiate a StringWriter
        StringWriter writer=new StringWriter();
        Template template = velocityEngine.getTemplate(sysRoot+basePath, "UTF-8");
        template.merge(velocityContext, stringWriter);
        return stringWriter.toString();
    }
}

 2   Load the template file from the classpath

 

package com.velocity.test;
import java.io.StringWriter;
import java.util.Properties;
import org.apache.velocity.VelocityContext;
import org.apache.velocity.app.VelocityEngine;
/**
 * Load template files from class (classpath)
 */
public class LoaderFromClass {
    public static void main(String[] args) throws Exception{
        //Initialization parameters
        Properties properties=new Properties();
        / / Set the velocity resource loading method to class
        properties.setProperty("resource.loader", "class");
        //Set the processing class when the velocity resource loading method is file
        properties.setProperty("class.resource.loader.class", "org.apache.velocity.runtime.resource.loader.ClasspathResourceLoader");
        //Instantiate a VelocityEngine object
        VelocityEngine velocityEngine=new VelocityEngine(properties);
        
        //Instantiate a VelocityContext
        VelocityContext context=new VelocityContext();
        //Put key values ​​into VelocityContext
        context.put("username", "张三");
        context.put("password", "123456789");
        context.put("age", "20");
        context.put("address", "Shaanxi Xi'an");
        context.put("blog", "http://blogjava.net/sxyx2008");
        //Instantiate a StringWriter
        StringWriter writer=new StringWriter();
        //Load the hello.vm template from the src directory
        //If there is a hello.vm file under the com.velocity.test package, the loading path is com/velocity/test/hello.vm
        velocityEngine.mergeTemplate("com/velocity/test/hello.vm", "gbk", context, writer);
        //velocityEngine.mergeTemplate("hello.vm", "gbk", context, writer);
        System.out.println(writer.toString());
    }
}

 

3  Load the template file from the jar file

public class VelocityTemplate {
    public static String getVelocityTemplate(String basePath) throws Exception {
        String sysRoot = VelocityTemplate.class.getResource("").getPath();
        //Initialization parameters
        Properties properties=new Properties();
        //Set the velocity resource loading method to jar
        properties.setProperty("resource.loader", "jar");
        //Set the processing class when the velocity resource loading method is file
        properties.setProperty("jar.resource.loader.class", "org.apache.velocity.runtime.resource.loader.JarResourceLoader");
        //Set the location of the jar package
        properties.setProperty("jar.resource.loader.path", "jar:file:/F:/quicksure_Server_Provider.jar");
        properties.put("input.encoding", "UTF-8");
        properties.put("output.encoding", "UTF-8");
        //Instantiate a VelocityEngine object
        VelocityEngine velocityEngine = new VelocityEngine(properties);
        //Instantiate a VelocityContext
        VelocityContext velocityContext = new VelocityContext();
        //Put key values ​​into VelocityContext
        context.put("username", "张三");
        context.put("password", "123456789");
        context.put("age", "20");
        //Instantiate a StringWriter
        StringWriter writer=new StringWriter();
        Template template = velocityEngine.getTemplate("com/quicksure/insurance/velocity/template/"+basePath, "UTF-8");
        template.merge(velocityContext, stringWriter);
        return stringWriter.toString();
    }
}