IO Foundation 6-解压缩zip文件

 

需求：

这一步也非常简单，主要是demo下ZipEntry的用法，就是把一个以zip扩展名结尾的文件进行解压缩。

所以我就直接贴上代码了：

 

实现：

 

/**

* This class will handle the folder zipper related operations

*

 * @author cwang58

* @created date: Aug 4, 2012

*/

public class FolderZipper implements IFolderZipper {



         private static Logger logger = LoggerFactory.getLogger(FolderZipper.class);



         /**

         * to unzip a zip file ,it will read all the entries in the zip file if the

         * entry is a folder ,then it will created a folder structure (including the

         * parent folder structure) if the entry is a file ,then it use file output

         * stream to output this file

         *

          * @param zipFileName

         *            the zip file name

         * @param destPath

         *            the path that we want to zip to

         */

         public void unzip(String zipFileName, String destPath) throws Exception {



                 // verify the parameters

                 if (zipFileName == null || zipFileName.trim().equals(EMPTY_STRING)) {

                          if (logger.isErrorEnabled()) {

                                   logger.error("zipFileName parameter can't be null");

                          }

                          throw new ParameterNullException(ZIP_UNZIP_ERROR);

                 }



                 if (destPath == null) {



                          if (logger.isErrorEnabled()) {

                                   logger.error("destPath parameter can't be null");

                          }

                          throw new ParameterNullException("ZIP_UNZIP_ERROR");

                 }



                 // verify the zip file 's file extension (only support ZIP)

                 if (!zipFileName.trim().endsWith(ZIP_EXTENSION)) {



                          if (logger.isErrorEnabled()) {

                                   logger.error("the zip file MUST BE end with zip suffix");

                          }

                          throw new ParameterInvalidException(ZIP_UNZIP_ERROR);

                 }



                 try {



                          FileInputStream fis = new FileInputStream(zipFileName);

                          ZipInputStream zis = new ZipInputStream(fis);

                          ZipEntry ze = null;



                          if (destPath.equals(DOT))

                                   destPath = EMPTY_STRING;



                          while ((ze = zis.getNextEntry()) != null) {



                                   // if the zipEntry is a folder

                                   // then must create the folder structure

                                   if (ze.isDirectory()) {



                                            if (logger.isDebugEnabled()) {

                                                     logger.debug("Processing folder:" + ze.getName());

                                            }



                                            // construct the dirName by string concating the destpath

                                            // and the foldername

                                            String dirName = destPath + ze.getName();



                                            // creating the folder structure

                                            File f = new File(dirName);

                                            f.mkdirs();



                                            if (logger.isDebugEnabled()) {

                                                    logger.debug("The folder " + f.getAbsolutePath()

                                                                      + " is created");

                                            }

                                   }



                                   // if the zipEntry file is a file

                                   // then use a FileOutputStream to write this file

                                   else {

                                            if (logger.isDebugEnabled()) {

                                                    logger.debug("Processing file: " + ze.getName());

                                            }



                                            // construct the fileName by string concating the destpath

                                            // and the foldername

                                           String fileName = destPath + ze.getName();

                                            File f = new File(fileName);



                                            // open a FileOutputStream to write this file

                                            FileOutputStream fos = new FileOutputStream(f);

                                            int tmp = -1;

                                            while ((tmp = zis.read()) != -1) {

                                                    fos.write(tmp);

                                            }

                                            zis.closeEntry();

                                            fos.close();



                                            if (logger.isDebugEnabled()) {

                                                    logger.debug("The file " + f.getAbsolutePath()

                                                                      + " is created");

                                            }

                                   }

                          }

                          zis.close();



                 } catch (FileNotFoundException ex) {



                          if (logger.isErrorEnabled()) {

                                   logger.error("file not found");

                          }

                          throw new InvalidFolderZipperException(ZIP_UNZIP_ERROR, ex);



                 } catch (IOException ex) {



                          if (logger.isErrorEnabled()) {

                                   logger.error("io exception occured");

                          }



                          throw new InvalidFolderZipperException(ZIP_UNZIP_ERROR,

                                            ex);

                 }

         }



}

 

(1)在47-93行还是对入参进行严格的检查。

(2)第103行打开了一个ZipInputStream，然后在第115行对于这个zip文件里的所有的条目进行遍历。

(3)第119-159行对于条目是一个目录的情况进行了处理，它必须去相应的创建目录结构

(4)第163-215行对于条目是个文件的情况进行了处理，它打开一个文件输出流然后写这个Zip的文件条目到目标目录下相应的位置。