一Java 解压rar文件

1.1 引入pom依赖

<dependency>
            <groupId>com.github.junrar</groupId>
            <artifactId>junrar</artifactId>
            <version>4.0.0</version>
</dependency>

1.2 解压代码

             // 加载rar文件
            Archive archive = new Archive(new File("/home/a.rar"));
            List<FileHeader> fileHeaders = archive.getFileHeaders();
            if (fileHeaders == null) {
                throw new BizException("压缩文件中不存在文件");
            }
            // 解压第一个文件
            FileHeader fileHeader = fileHeaders.get(0);
           OutputStream outputStream = null;
            try {
                outputStream = new FileOutputStream();
                 // 将解压的文件放入outputStream
                 archive.extractFile(fileHeader, outputStream);
                 // 伪代码：写入磁盘
                  write(outputStream)
            }catch (Exception e) {
                throw e;
            }finally {
                if (outputStream != null) {
                    outputStream.close();
                }
            }

二、解压zip

2.1 引入pom依赖

<dependency>
                <groupId>org.apache.commons</groupId>
                <artifactId>commons-compress</artifactId>
                <version>1.18</version>
</dependency>

2.2 代码

2.3 加载内存中的zip文件

             //bytes表示内存中zip文件
            SeekableInMemoryByteChannel inMemoryByteChannel = new SeekableInMemoryByteChannel(bytes);
            ZipFile zipFile = new ZipFile(inMemoryByteChannel);
            // 判断zip中是否还有剩余的文件
            while (zipFile.getEntries().hasMoreElements()) {
                //提取文件
                ZipArchiveEntry zipArchiveEntry  = zipFile.getEntries().nextElement();
                //获取输入流
                InputStream zipFileInputStream = zipFile.getInputStream(zipArchiveEntry);
                FileOutputStream outputStream = new FileOutputStream();
                IOUtils.copy(zipFileInputStream, outputStream);
                //伪代码：写入磁盘
                write(outputStream);
                outputStream.close();

2.4 加载磁盘中的zip文件

ZipFile zipFile = new ZipFile(new File("/home/a.zip"));
//剩余步骤与2.3一致
...

参考文档：https://commons.apache.org/proper/commons-compress/examples.html