使用epublib提取epub信息

### 1、引入依赖

最新版获取：https://mvnrepository.com

<dependency>
 <groupId>com.positiondev.epublib</groupId>
 <artifactId>epublib-core</artifactId>
 <version>3.1</version>
 </dependency>
		
### 2、实例代码

```java
import nl.siegmann.epublib.domain.*;
import nl.siegmann.epublib.epub.EpubReader;

import java.io.File;
import java.io.FileInputStream;
import java.io.IOException;
import java.io.InputStream;
import java.nio.charset.StandardCharsets;
import java.util.Collection;
import java.util.List;

public class EpubTest {
 public static void main(String[] args) {
 // epub文件
 File file = new File("1.epub");
 InputStream in = null;
 try {
 //从输入流当中读取epub格式文件
 EpubReader reader = new EpubReader();
 in = new FileInputStream(file);
 Book book = reader.readEpub(in);
 //获取到书本的头部信息
 Metadata metadata = book.getMetadata();
 System.out.println("FirstTitle为：" + metadata.getFirstTitle());
 //获取到书本的全部资源
 Resources resources = book.getResources();
 System.out.println("所有资源数量为：" + resources.size());
 //获取所有的资源数据
 Collection<String> allHrefs = resources.getAllHrefs();
 for (String href : allHrefs) {
 Resource resource = resources.getByHref(href);
 //data就是资源的内容数据，可能是css,html,图片等等
 byte[] data = resource.getData();
 // 获取到内容的类型 css,html,还是图片
 MediaType mediaType = resource.getMediaType();
 }
 //获取到书本的内容资源
 List<Resource> contents = book.getContents();
 System.out.println("内容资源数量为：" + contents.size());
 //获取到书本的spine资源 线性排序
 Spine spine = book.getSpine();
 System.out.println("spine资源数量为：" + spine.size());
 //通过spine获取所有的数据
 List<SpineReference> spineReferences = spine.getSpineReferences();
 StringBuilder sb = new StringBuilder();
 for (SpineReference spineReference : spineReferences) {
 Resource resource = spineReference.getResource();
 //data就是资源的内容数据，可能是css,html,图片等等
 byte[] data = resource.getData();
 sb.append(new String(data, StandardCharsets.UTF_8)).append(" ");
 System.out.println(new String(data, StandardCharsets.UTF_8));
 // 获取到内容的类型 css,html,还是图片
 MediaType mediaType = resource.getMediaType();
 }

//获取到书本的目录资源
 TableOfContents tableOfContents = book.getTableOfContents();
 System.out.println("目录资源数量为：" + tableOfContents.size());
 //获取到目录对应的资源数据
 List<TOCReference> tocReferences = tableOfContents.getTocReferences();
 for (TOCReference tocReference : tocReferences) {
 Resource resource = tocReference.getResource();
 //data就是资源的内容数据，可能是css,html,图片等等
 byte[] data = resource.getData();
 // 获取到内容的类型 css,html,还是图片
 MediaType mediaType = resource.getMediaType();
 if (tocReference.getChildren().size() > 0) {
 //获取子目录的内容
 }
 }
 } catch (Exception e) {
 e.printStackTrace();
 } finally {
 //一定要关闭资源
 try {
 if (in != null) {
 in.close();
 }
 } catch (IOException e) {
 e.printStackTrace();
 }
 }
 }
}

```