FreeMarker 是一款 模板引擎： 即一种基于模板和要改变的数据， 并用来生成输出文本(HTML网页，电子邮件，配置文件，源代码等)的通用工具。 它不是面向最终用户的，而是一个Java类库，是一款程序员可以嵌入他们所开发产品的组件。
freemarker生成静态页面步骤
依赖
<dependencies>
<dependency>
<groupId>org.springframework.boot</groupId>
<artifactId>spring-boot-starter-web</artifactId>
</dependency>
<dependency>
<groupId>org.springframework.boot</groupId>
<artifactId>spring-boot-starter-freemarker</artifactId>
</dependency>
<dependency>
<groupId>org.springframework.boot</groupId>
<artifactId>spring-boot-starter-test</artifactId>
</dependency>
<!-- lombok -->
<dependency>
<groupId>org.projectlombok</groupId>
<artifactId>lombok</artifactId>
</dependency>
<!-- apache 对 java io 的封装工具库 -->
<dependency>
<groupId>org.apache.commons</groupId>
<artifactId>commons-io</artifactId>
<version>1.3.2</version>
</dependency>
</dependencies>
模型类
import lombok.Data;
import java.util.Date;
@Data
public class Student {
private String name;//姓名
private int age;//年龄
private Date birthday;//生日
private Float money;//钱包
}
模板
01-basic.ftl
<!DOCTYPE html>
<html>
<head>
<meta charset="utf-8">
<title>Hello World!</title>
</head>
<body>
<b>普通文本 String 展示：</b><br><br>
Hello ${name} <br>
<hr>
<b>对象Student中的数据展示：</b><br/>
姓名：${stu.name}<br/>
年龄：${stu.age}
<hr>
</body>
</html>
application.xml中freemarker配置
freemarker:
cache: false #关闭模板缓存，方便测试
settings:
template_update_delay: 0 #检查模板更新延迟时间，设置为0表示立即检查，如果时间大于0会有缓存不方便进行模板测试
suffix: .ftl #指定Freemarker模板文件的后缀名
template-loader-path: classpath:/templates #模板存放位置
具体实现生成静态页面到d:/list.html
import com.heima.freemarker.FreemarkerDemoApplication;
import com.heima.freemarker.entity.Student;
import freemarker.template.Configuration;
import freemarker.template.Template;
import freemarker.template.TemplateException;
import org.junit.Test;
import org.junit.runner.RunWith;
import org.springframework.beans.factory.annotation.Autowired;
import org.springframework.boot.test.context.SpringBootTest;
import org.springframework.test.context.junit4.SpringRunner;
import java.io.FileWriter;
import java.io.IOException;
import java.util.*;
@SpringBootTest(classes = FreemarkerDemoApplication.class)
@RunWith(SpringRunner.class)
public class FreemarkerTest {
@Autowired
private Configuration configuration;
@Test
public void test() throws IOException, TemplateException {
//freemarker的模板对象，获取模板
Template template = configuration.getTemplate("01-basic.ftl");
Map params = getData();
//合成
//第一个参数 数据模型
//第二个参数 输出流
template.process(params, new FileWriter("d:/list.html"));
}
private Map getData() {
Map<String, Object> map = new HashMap<>();
//小强对象模型数据
Student stu1 = new Student();
stu1.setName("小强");
stu1.setAge(18);
stu1.setMoney(1000.86f);
stu1.setBirthday(new Date());
//小红对象模型数据
Student stu2 = new Student();
stu2.setName("小红");
stu2.setMoney(200.1f);
stu2.setAge(19);
//将两个对象模型数据存放到List集合中
List<Student> stus = new ArrayList<>();
stus.add(stu1);
stus.add(stu2);
//向map中存放List集合数据
map.put("stus", stus);
//创建Map数据
HashMap<String, Student> stuMap = new HashMap<>();
stuMap.put("stu1", stu1);
stuMap.put("stu2", stu2);
//向map中存放Map数据
map.put("stuMap", stuMap);
//返回Map
return map;
}
}
对象存储服务MinIO
MinIO基于Apache License v2.0开源协议的对象存储服务，可以做为云存储的解决方案用来保存海量的图片，视频，文档。由于采用Golang实现，服务端可以工作在Windows,Linux, OS X和FreeBSD上。配置简单，基本是复制可执行程序，单行命令可以运行起来。
这里提供将minio上传封装成一个模块
pom.xml
<dependencies>
<dependency>
<groupId>org.springframework.boot</groupId>
<artifactId>spring-boot-autoconfigure</artifactId>
</dependency>
<dependency>
<groupId>io.minio</groupId>
<artifactId>minio</artifactId>
<version>7.1.0</version>
</dependency>
<dependency>
<groupId>org.springframework.boot</groupId>
<artifactId>spring-boot-starter</artifactId>
</dependency>
<dependency>
<groupId>org.springframework.boot</groupId>
<artifactId>spring-boot-configuration-processor</artifactId>
<optional>true</optional>
</dependency>
<dependency>
<groupId>org.springframework.boot</groupId>
<artifactId>spring-boot-starter-actuator</artifactId>
</dependency>
</dependencies>
MinIOConfig
@Data
@Configuration
@EnableConfigurationProperties({MinIOConfigProperties.class})
//当引入FileStorageService接口时
@ConditionalOnClass(FileStorageService.class)
public class MinIOConfig {
@Autowired
private MinIOConfigProperties minIOConfigProperties;
@Bean
public MinioClient buildMinioClient() {
return MinioClient
.builder()
.credentials(minIOConfigProperties.getAccessKey(), minIOConfigProperties.getSecretKey())
.endpoint(minIOConfigProperties.getEndpoint())
.build();
}
}
MinIOConfigProperties
@Data
@ConfigurationProperties(prefix = "minio") // 文件上传 配置前缀file.oss
public class MinIOConfigProperties implements Serializable {
private String accessKey;
private String secretKey;
private String bucket;
private String endpoint;
private String readPath;
}
FileStorageService
public interface FileStorageService {
/**
* 上传图片文件
* @param prefix 文件前缀
* @param filename 文件名
* @param inputStream 文件流
* @return 文件全路径
*/
public String uploadImgFile(String prefix, String filename,InputStream inputStream);
/**
* 上传html文件
* @param prefix 文件前缀
* @param filename 文件名
* @param inputStream 文件流
* @return 文件全路径
*/
public String uploadHtmlFile(String prefix, String filename,InputStream inputStream);
/**
* 删除文件
* @param pathUrl 文件全路径
*/
public void delete(String pathUrl);
/**
* 下载文件
* @param pathUrl 文件全路径
* @return
*
*/
public byte[] downLoadFile(String pathUrl);
}
MinIOFileStorageService
@Slf4j
@EnableConfigurationProperties(MinIOConfigProperties.class)
@Import(MinIOConfig.class)
public class MinIOFileStorageService implements FileStorageService {
@Autowired
private MinioClient minioClient;
@Autowired
private MinIOConfigProperties minIOConfigProperties;
private final static String separator = "/";
/**
* @param dirPath
* @param filename yyyy/mm/dd/file.jpg
* @return
*/
public String builderFilePath(String dirPath,String filename) {
StringBuilder stringBuilder = new StringBuilder(50);
if(!StringUtils.isEmpty(dirPath)){
stringBuilder.append(dirPath).append(separator);
}
SimpleDateFormat sdf = new SimpleDateFormat("yyyy/MM/dd");
String todayStr = sdf.format(new Date());
stringBuilder.append(todayStr).append(separator);
stringBuilder.append(filename);
return stringBuilder.toString();
}
/**
* 上传图片文件
* @param prefix 文件前缀
* @param filename 文件名
* @param inputStream 文件流
* @return 文件全路径
*/
@Override
public String uploadImgFile(String prefix, String filename,InputStream inputStream) {
String filePath = builderFilePath(prefix, filename);
try {
PutObjectArgs putObjectArgs = PutObjectArgs.builder()
.object(filePath)
.contentType("image/jpg")
.bucket(minIOConfigProperties.getBucket()).stream(inputStream,inputStream.available(),-1)
.build();
minioClient.putObject(putObjectArgs);
StringBuilder urlPath = new StringBuilder(minIOConfigProperties.getReadPath());
urlPath.append(separator+minIOConfigProperties.getBucket());
urlPath.append(separator);
urlPath.append(filePath);
return urlPath.toString();
}catch (Exception ex){
log.error("minio put file error.",ex);
throw new RuntimeException("上传文件失败");
}
}
/**
* 上传html文件
* @param prefix 文件前缀
* @param filename 文件名
* @param inputStream 文件流
* @return 文件全路径
*/
@Override
public String uploadHtmlFile(String prefix, String filename,InputStream inputStream) {
String filePath = builderFilePath(prefix, filename);
try {
PutObjectArgs putObjectArgs = PutObjectArgs.builder()
.object(filePath)
.contentType("text/html")
.bucket(minIOConfigProperties.getBucket()).stream(inputStream,inputStream.available(),-1)
.build();
minioClient.putObject(putObjectArgs);
StringBuilder urlPath = new StringBuilder(minIOConfigProperties.getReadPath());
urlPath.append(separator+minIOConfigProperties.getBucket());
urlPath.append(separator);
urlPath.append(filePath);
return urlPath.toString();
}catch (Exception ex){
log.error("minio put file error.",ex);
ex.printStackTrace();
throw new RuntimeException("上传文件失败");
}
}
/**
* 删除文件
* @param pathUrl 文件全路径
*/
@Override
public void delete(String pathUrl) {
String key = pathUrl.replace(minIOConfigProperties.getEndpoint()+"/","");
int index = key.indexOf(separator);
String bucket = key.substring(0,index);
String filePath = key.substring(index+1);
// 删除Objects
RemoveObjectArgs removeObjectArgs = RemoveObjectArgs.builder().bucket(bucket).object(filePath).build();
try {
minioClient.removeObject(removeObjectArgs);
} catch (Exception e) {
log.error("minio remove file error. pathUrl:{}",pathUrl);
e.printStackTrace();
}
}
/**
* 下载文件
* @param pathUrl 文件全路径
* @return 文件流
*
*/
@Override
public byte[] downLoadFile(String pathUrl) {
String key = pathUrl.replace(minIOConfigProperties.getEndpoint()+"/","");
int index = key.indexOf(separator);
String bucket = key.substring(0,index);
String filePath = key.substring(index+1);
InputStream inputStream = null;
try {
inputStream = minioClient.getObject(GetObjectArgs.builder().bucket(minIOConfigProperties.getBucket()).object(filePath).build());
} catch (Exception e) {
log.error("minio down file error. pathUrl:{}",pathUrl);
e.printStackTrace();
}
ByteArrayOutputStream byteArrayOutputStream = new ByteArrayOutputStream();
byte[] buff = new byte[100];
int rc = 0;
while (true) {
try {
if (!((rc = inputStream.read(buff, 0, 100)) > 0)) break;
} catch (IOException e) {
e.printStackTrace();
}
byteArrayOutputStream.write(buff, 0, rc);
}
return byteArrayOutputStream.toByteArray();
}
}
spring.factories
org.springframework.boot.autoconfigure.EnableAutoConfiguration=\
com.file.service.impl.MinIOFileStorageService
application.xml中minio配置
minio:
accessKey: minio
secretKey: minio123
bucket: leadnews
endpoint: http://192.168.200.130:9000
readPath: http://192.168.200.130:9000
freemarker生成的流文件存储到minio中实现
//根据模板获取模板对象
Template template = configuration.getTemplate("article.ftl");
//生成的静态页面暂时存储为一个二进制类型的字符串
StringWriter out = new StringWriter();
template.process(map, out);
//转换成字节流
InputStream is = new ByteArrayInputStream(out.toString().getBytes());
//上传到minio中并返回静态页面的访问路径
String staticUrl = fileStorageService.uploadHtmlFile("", fileId + ".html", is);
