本文讲述了Java SpringBoot整合Velocity实现代码预览和文件生成教程！具有很好的参考价值，希望对大家有所帮助。一起跟随六星小编过来看看吧，具体如下:

这里做一个简单的示例DEMO，实现一键打包zip，提供一种解决方案，实际需求可以按需所改，代码就三四个文件不上传上来了，下面贴出完整代码：

文件目录如下：

实体类User.java

省略 getter 和 setter 方法

package com.fun.demo.model;

/**

 * @author MrDJun 2020/10/21

 */

public class User {

    private Integer age;

    private String name;

    public User(Integer age, String name) {

        this.age = age;

        this.name = name;

    }

    public User(){}

}

VelocityUtils.java

package com.fun.demo.tool;

import com.fun.demo.model.User;

import org.apache.velocity.Template;

import org.apache.velocity.VelocityContext;

import org.apache.velocity.app.Velocity;

import org.slf4j.Logger;

import org.slf4j.LoggerFactory;

import org.apache.commons.io.IOUtils;

import java.io.ByteArrayOutputStream;

import java.io.IOException;

import java.io.StringWriter;

import java.util.Properties;

import java.util.zip.ZipEntry;

import java.util.zip.ZipOutputStream;

/**

 * @author MrDJun 2020/10/21

 */

public class VelocityUtils {

    private final static Logger log = LoggerFactory.getLogger(VelocityUtils.class);

    public static String previewCode() {

        initVelocity();

        User user = new User(18, "mrdjun");

        VelocityContext context = VelocityUtils.prepareContext(user);

        StringWriter sw = new StringWriter();

        Template tpl = Velocity.getTemplate("vm/xml/article.xml.vm", "UTF-8");

        tpl.merge(context, sw);

        return sw.toString();

    }

    public static byte[] downloadCode() {

        ByteArrayOutputStream outputStream = new ByteArrayOutputStream();

        ZipOutputStream zip = new ZipOutputStream(outputStream);

        generatorCode(zip);

        IOUtils.closeQuietly(zip);

        return outputStream.toByteArray();

    }

    public static void generatorCode(ZipOutputStream zip) {

        User user = new User(18, "mrdjun");

        initVelocity();

        VelocityContext context = VelocityUtils.prepareContext(user);

        StringWriter sw = new StringWriter();

        Template tpl = Velocity.getTemplate("vm/xml/article.xml.vm", "UTF-8");

        tpl.merge(context, sw);

        try {

            // 添加到zip

            zip.putNextEntry(new ZipEntry("article.xml"));

            IOUtils.write(sw.toString(), zip, "UTF-8");

            IOUtils.closeQuietly(sw);

            zip.flush();

            zip.closeEntry();

        } catch (IOException e) {

            log.error("渲染模板失败：{0}", e);

        }

    }

    public static VelocityContext prepareContext(User user) {

        VelocityContext velocityContext = new VelocityContext();

        velocityContext.put("age", user.getAge());

        velocityContext.put("name", user.getName());

        return velocityContext;

    }

    public static void initVelocity() {

        Properties p = new Properties();

        try {

            // 加载classpath目录下的vm文件

            p.setProperty("file.resource.loader.class", "org.apache.velocity.runtime.resource.loader.ClasspathResourceLoader");

            // 定义字符集

            p.setProperty(Velocity.ENCODING_DEFAULT, "UTF-8");

            p.setProperty(Velocity.OUTPUT_ENCODING, "UTF-8");

            // 初始化Velocity引擎，指定配置Properties

            Velocity.init(p);

        } catch (Exception e) {

            throw new RuntimeException(e);

        }

    }

}

CodeController.java

package com.fun.demo.controller;

import com.fun.demo.tool.VelocityUtils;

import org.apache.commons.io.IOUtils;

import org.springframework.web.bind.annotation.RequestMapping;

import org.springframework.web.bind.annotation.RestController;

import javax.servlet.http.HttpServletResponse;

import java.io.IOException;

/**

 * @author MrDJun 2020/10/21

 */

@RestController

public class CodeController {

    @RequestMapping("/download")

    public void download(HttpServletResponse response) throws IOException {

       byte[] data = VelocityUtils.downloadCode();

        genCode(response, data);

    }

    /**

     * 生成zip文件

     */

    private void genCode(HttpServletResponse response, byte[] data) throws IOException {

       response.reset();

        response.setHeader("Content-Disposition", "attachment; filename=\"fun.zip\"");

       response.addHeader("Content-Length", "" + data.length);

        response.setContentType("application/octet-stream; charset=UTF-8");

        IOUtils.write(data, response.getOutputStream());

    }

}

在创建一个SpringBoot的启动类

在resources下面创建一个vm文件夹，article.xml.vm

<?xml version="1.0" encoding="utf-8"?>

<DOCUMENT>

    我叫${name}，今年${age}岁

</DOCUMENT>

pom.xml

我这里的全部依赖如下，按需所取：

<?xml version="1.0" encoding="UTF-8"?>

<project xmlns="http://maven.apache.org/POM/4.0.0" xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance"

         xsi:schemaLocation="http://maven.apache.org/POM/4.0.0 https://maven.apache.org/xsd/maven-4.0.0.xsd">

    <modelVersion>4.0.0</modelVersion>

    <parent>

        <groupId>org.springframework.boot</groupId>

        <artifactId>spring-boot-starter-parent</artifactId>

        <version>2.1.5.RELEASE</version>

        <relativePath/>

    </parent>

    <groupId>com.fun</groupId>

    <artifactId>demo</artifactId>

    <version>0.0.1-SNAPSHOT</version>

    <name>demo</name>

    <description>Demo project for Spring Boot</description>

    <properties>

        <java.version>1.8</java.version>

    </properties>

    <dependencies>

        <!-- SpringBoot 核心包 -->

        <dependency>

            <groupId>org.springframework.boot</groupId>

            <artifactId>spring-boot-starter</artifactId>

        </dependency>

        <dependency>

            <groupId>org.springframework.boot</groupId>

            <artifactId>spring-boot-starter-web</artifactId>

        </dependency>

        <!--Spring框架基本的核心工具-->

        <dependency>

            <groupId>org.springframework</groupId>

            <artifactId>spring-context-support</artifactId>

        </dependency>

        <!--常用工具类 -->

        <dependency>

            <groupId>org.apache.commons</groupId>

            <artifactId>commons-lang3</artifactId>

        </dependency>

       <!--io常用工具类 -->

        <dependency>

            <groupId>commons-io</groupId>

            <artifactId>commons-io</artifactId>

            <version>2.5</version>

        </dependency>

        <!--velocity代码生成使用模板 -->

        <dependency>

            <groupId>org.apache.velocity</groupId>

            <artifactId>velocity</artifactId>

            <version>1.7</version>

        </dependency>

        <!-- SpringBoot 测试 -->

        <dependency>

            <groupId>org.springframework.boot</groupId>

            <artifactId>spring-boot-starter-test</artifactId>

            <scope>test</scope>

        </dependency>

    </dependencies>

    <build>

        <plugins>

            <plugin>

                <groupId>org.springframework.boot</groupId>

                <artifactId>spring-boot-maven-plugin</artifactId>

            </plugin>

        </plugins>

    </build>

</project>

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