FileUtils工具类常用方法

ゝ一纸荒年。 2022-05-13 15:16 451阅读 0赞

# **文件操作工具类（FileUtils）** #

**使用 apache 的`commons-io`包下的FileUtils，**import org.apache.commons.io.FileUtils;

**下载地址：[http://commons.apache.org/proper/commons-io/download\_io.cgi][http_commons.apache.org_proper_commons-io_download_io.cgi]**

**官方API文档：[http://commons.apache.org/proper/commons-io/apidocs/org/apache/commons/io/FileUtils.html][http_commons.apache.org_proper_commons-io_apidocs_org_apache_commons_io_FileUtils.html]**

静态方法可以直接使用类名使用

maven 创建的java工程，导入依赖

<dependency>
            <groupId>commons-fileupload</groupId>
            <artifactId>commons-fileupload</artifactId>
            <version>1.3.3</version>
        </dependency>

###   ![watermark_type_ZmFuZ3poZW5naGVpdGk_shadow_10_text_aHR0cHM6Ly9ibG9nLmNzZG4ubmV0L3FxXzQyNDAyODU0_size_27_color_FFFFFF_t_70][] ###

### 一、拷贝文件 ###

<table> 
 <tbody> 
  <tr> 
   <td><code><span style="color:#f33b45;">static</span> void</code></td> 
   <td><code><a href="http://commons.apache.org/proper/commons-io/apidocs/org/apache/commons/io/FileUtils.html#copyFile-java.io.File-java.io.File-" rel="nofollow"><span style="color:#f33b45;">copyFile</span></a>(<a href="http://docs.oracle.com/javase/7/docs/api/java/io/File.html?is-external=true" rel="nofollow">File</a>&nbsp;srcFile,&nbsp;<a href="http://docs.oracle.com/javase/7/docs/api/java/io/File.html?is-external=true" rel="nofollow">File</a>&nbsp;destFile)</code> <p>Copies a file to a new location preserving the file date.</p> </td> 
  </tr> 
  <tr> 
   <td><code>static void</code></td> 
   <td><code><a href="http://commons.apache.org/proper/commons-io/apidocs/org/apache/commons/io/FileUtils.html#copyFile-java.io.File-java.io.File-boolean-" rel="nofollow">copyFile</a>(<a href="http://docs.oracle.com/javase/7/docs/api/java/io/File.html?is-external=true" rel="nofollow">File</a>&nbsp;srcFile,&nbsp;<a href="http://docs.oracle.com/javase/7/docs/api/java/io/File.html?is-external=true" rel="nofollow">File</a>&nbsp;destFile, boolean&nbsp;preserveFileDate)</code> <p>Copies a file to a new location.</p> </td> 
  </tr> 
  <tr> 
   <td><code>static long</code></td> 
   <td><code><a href="http://commons.apache.org/proper/commons-io/apidocs/org/apache/commons/io/FileUtils.html#copyFile-java.io.File-java.io.OutputStream-" rel="nofollow">copyFile</a>(<a href="http://docs.oracle.com/javase/7/docs/api/java/io/File.html?is-external=true" rel="nofollow">File</a>&nbsp;input,&nbsp;<a href="http://docs.oracle.com/javase/7/docs/api/java/io/OutputStream.html?is-external=true" rel="nofollow">OutputStream</a>&nbsp;output)</code> <p>Copy bytes from a&nbsp;<code>File</code>&nbsp;to an&nbsp;<code>OutputStream</code>.</p> </td> 
  </tr> 
  <tr> 
   <td><code>static void</code></td> 
   <td><code><a href="http://commons.apache.org/proper/commons-io/apidocs/org/apache/commons/io/FileUtils.html#copyFileToDirectory-java.io.File-java.io.File-" rel="nofollow">copyFileToDirectory</a>(<a href="http://docs.oracle.com/javase/7/docs/api/java/io/File.html?is-external=true" rel="nofollow">File</a>&nbsp;srcFile,&nbsp;<a href="http://docs.oracle.com/javase/7/docs/api/java/io/File.html?is-external=true" rel="nofollow">File</a>&nbsp;destDir)</code> <p>Copies a file to a directory preserving the file date.</p> </td> 
  </tr> 
  <tr> 
   <td><code>static void</code></td> 
   <td><code><a href="http://commons.apache.org/proper/commons-io/apidocs/org/apache/commons/io/FileUtils.html#copyFileToDirectory-java.io.File-java.io.File-boolean-" rel="nofollow">copyFileToDirectory</a>(<a href="http://docs.oracle.com/javase/7/docs/api/java/io/File.html?is-external=true" rel="nofollow">File</a>&nbsp;srcFile,&nbsp;<a href="http://docs.oracle.com/javase/7/docs/api/java/io/File.html?is-external=true" rel="nofollow">File</a>&nbsp;destDir, boolean&nbsp;preserveFileDate)</code> <p>Copies a file to a directory optionally preserving the file date.</p> </td> 
  </tr> 
  <tr> 
   <td><code>static void</code></td> 
   <td><code><a href="http://commons.apache.org/proper/commons-io/apidocs/org/apache/commons/io/FileUtils.html#copyInputStreamToFile-java.io.InputStream-java.io.File-" rel="nofollow">copyInputStreamToFile</a>(<a href="http://docs.oracle.com/javase/7/docs/api/java/io/InputStream.html?is-external=true" rel="nofollow">InputStream</a>&nbsp;source,&nbsp;<a href="http://docs.oracle.com/javase/7/docs/api/java/io/File.html?is-external=true" rel="nofollow">File</a>&nbsp;destination)</code> <p>Copies bytes from an&nbsp;<a href="http://docs.oracle.com/javase/7/docs/api/java/io/InputStream.html?is-external=true" rel="nofollow"><code>InputStream</code></a>&nbsp;<code>source</code>&nbsp;to a file&nbsp;<code>destination</code>.</p> </td> 
  </tr> 
  <tr> 
   <td><code>static void</code></td> 
   <td><code><a href="http://commons.apache.org/proper/commons-io/apidocs/org/apache/commons/io/FileUtils.html#copyToDirectory-java.io.File-java.io.File-" rel="nofollow">copyToDirectory</a>(<a href="http://docs.oracle.com/javase/7/docs/api/java/io/File.html?is-external=true" rel="nofollow">File</a>&nbsp;src,&nbsp;<a href="http://docs.oracle.com/javase/7/docs/api/java/io/File.html?is-external=true" rel="nofollow">File</a>&nbsp;destDir)</code> <p>Copies a file or directory to within another directory preserving the file dates.</p> </td> 
  </tr> 
  <tr> 
   <td><code>static void</code></td> 
   <td><code><a href="http://commons.apache.org/proper/commons-io/apidocs/org/apache/commons/io/FileUtils.html#copyToDirectory-java.lang.Iterable-java.io.File-" rel="nofollow">copyToDirectory</a>(<a href="http://docs.oracle.com/javase/7/docs/api/java/lang/Iterable.html?is-external=true" rel="nofollow">Iterable</a>&lt;<a href="http://docs.oracle.com/javase/7/docs/api/java/io/File.html?is-external=true" rel="nofollow">File</a>&gt;&nbsp;srcs,&nbsp;<a href="http://docs.oracle.com/javase/7/docs/api/java/io/File.html?is-external=true" rel="nofollow">File</a>&nbsp;destDir)</code> <p>Copies a files to a directory preserving each file's date.</p> </td> 
  </tr> 
  <tr> 
   <td><code>static void</code></td> 
   <td><code><a href="http://commons.apache.org/proper/commons-io/apidocs/org/apache/commons/io/FileUtils.html#copyToFile-java.io.InputStream-java.io.File-" rel="nofollow">copyToFile</a>(<a href="http://docs.oracle.com/javase/7/docs/api/java/io/InputStream.html?is-external=true" rel="nofollow">InputStream</a>&nbsp;source,&nbsp;<a href="http://docs.oracle.com/javase/7/docs/api/java/io/File.html?is-external=true" rel="nofollow">File</a>&nbsp;destination)</code> <p>Copies bytes from an&nbsp;<a href="http://docs.oracle.com/javase/7/docs/api/java/io/InputStream.html?is-external=true" rel="nofollow"><code>InputStream</code></a>&nbsp;<code>source</code>&nbsp;to a file&nbsp;<code>destination</code>.</p> </td> 
  </tr> 
  <tr> 
   <td><code>static void</code></td> 
   <td><code><a href="http://commons.apache.org/proper/commons-io/apidocs/org/apache/commons/io/FileUtils.html#copyURLToFile-java.net.URL-java.io.File-" rel="nofollow">copyURLToFile</a>(<a href="http://docs.oracle.com/javase/7/docs/api/java/net/URL.html?is-external=true" rel="nofollow">URL</a>&nbsp;source,&nbsp;<a href="http://docs.oracle.com/javase/7/docs/api/java/io/File.html?is-external=true" rel="nofollow">File</a>&nbsp;destination)</code> <p>Copies bytes from the URL&nbsp;<code>source</code>&nbsp;to a file&nbsp;<code>destination</code>.</p> </td> 
  </tr> 
  <tr> 
   <td><code>static void</code></td> 
   <td><code><a href="http://commons.apache.org/proper/commons-io/apidocs/org/apache/commons/io/FileUtils.html#copyURLToFile-java.net.URL-java.io.File-int-int-" rel="nofollow">copyURLToFile</a>(<a href="http://docs.oracle.com/javase/7/docs/api/java/net/URL.html?is-external=true" rel="nofollow">URL</a>&nbsp;source,&nbsp;<a href="http://docs.oracle.com/javase/7/docs/api/java/io/File.html?is-external=true" rel="nofollow">File</a>&nbsp;destination, int&nbsp;connectionTimeout, int&nbsp;readTimeout)</code> <p>Copies bytes from the URL&nbsp;<code>source</code>&nbsp;to a file&nbsp;<code>destination</code>.</p> </td> 
  </tr> 
 </tbody> 
</table>

**1）拷贝文件到文件：`copyFile(File srcFile, File destFile)`**

File file = new File("E:\\java\\file01\\abc雪.jpg");
    		String destFilePath = "E:\\java\\file02";
    		String destFileName = "abc雪02.jpg";
    		try {
    			FileUtils fileUtils = new FileUtils();
    			//文件拷贝到新的位置并保存文件的日期。
    			fileUtils.copyFile(file, new File(destFilePath,destFileName));
    			System.out.println("文件拷贝成功");
    		} catch (IOException e) {
    			e.printStackTrace();
    			System.out.println(e.getMessage());
    		}

**2）拷贝文件到字节输出流。：**`copyFile(File input, OutputStream output)`

String destFileName = "abc雪03.jpg";
    //从文件copy to an字节输出流。
    FileUtils.copyFile(file, new FileOutputStream(new File(destFilePath,destFileName)));

**3）拷贝文件到文件的目录保存文件的日期：**`copyFileToDirectory(File srcFile, File destDir)`

`  拷贝的文件名无法自定义，和原文件名一样`

//拷贝文件到文件的目录保持文件的日期。
    FileUtils.copyFileToDirectory(file, new File(destFilePath));

![70][]

## ##

### 二、拷贝目录及文件 ###

<table> 
 <tbody> 
  <tr> 
   <td><code>static void</code></td> 
   <td><code><a href="http://commons.apache.org/proper/commons-io/apidocs/org/apache/commons/io/FileUtils.html#copyDirectory-java.io.File-java.io.File-" rel="nofollow"><span style="color:#f33b45;">copyDirectory</span></a>(<a href="http://docs.oracle.com/javase/7/docs/api/java/io/File.html?is-external=true" rel="nofollow">File</a>&nbsp;srcDir,&nbsp;<a href="http://docs.oracle.com/javase/7/docs/api/java/io/File.html?is-external=true" rel="nofollow">File</a>&nbsp;destDir)</code> <p>Copies a whole directory to a new location preserving the file dates.</p> </td> 
  </tr> 
  <tr> 
   <td><code>static void</code></td> 
   <td><code><a href="http://commons.apache.org/proper/commons-io/apidocs/org/apache/commons/io/FileUtils.html#copyDirectory-java.io.File-java.io.File-boolean-" rel="nofollow">copyDirectory</a>(<a href="http://docs.oracle.com/javase/7/docs/api/java/io/File.html?is-external=true" rel="nofollow">File</a>&nbsp;srcDir,&nbsp;<a href="http://docs.oracle.com/javase/7/docs/api/java/io/File.html?is-external=true" rel="nofollow">File</a>&nbsp;destDir, boolean&nbsp;preserveFileDate)</code> <p>Copies a whole directory to a new location.</p> </td> 
  </tr> 
  <tr> 
   <td><code>static void</code></td> 
   <td><code><a href="http://commons.apache.org/proper/commons-io/apidocs/org/apache/commons/io/FileUtils.html#copyDirectory-java.io.File-java.io.File-java.io.FileFilter-" rel="nofollow"><span style="color:#f33b45;">copyDirectory</span></a>(<a href="http://docs.oracle.com/javase/7/docs/api/java/io/File.html?is-external=true" rel="nofollow">File</a>&nbsp;srcDir,&nbsp;<a href="http://docs.oracle.com/javase/7/docs/api/java/io/File.html?is-external=true" rel="nofollow">File</a>&nbsp;destDir,&nbsp;<a href="http://docs.oracle.com/javase/7/docs/api/java/io/FileFilter.html?is-external=true" rel="nofollow">FileFilter</a>&nbsp;filter)</code> <p>Copies a filtered directory to a new location preserving the file dates.</p> </td> 
  </tr> 
  <tr> 
   <td><code>static void</code></td> 
   <td><code><a href="http://commons.apache.org/proper/commons-io/apidocs/org/apache/commons/io/FileUtils.html#copyDirectory-java.io.File-java.io.File-java.io.FileFilter-boolean-" rel="nofollow">copyDirectory</a>(<a href="http://docs.oracle.com/javase/7/docs/api/java/io/File.html?is-external=true" rel="nofollow">File</a>&nbsp;srcDir,&nbsp;<a href="http://docs.oracle.com/javase/7/docs/api/java/io/File.html?is-external=true" rel="nofollow">File</a>&nbsp;destDir,&nbsp;<a href="http://docs.oracle.com/javase/7/docs/api/java/io/FileFilter.html?is-external=true" rel="nofollow">FileFilter</a>&nbsp;filter, boolean&nbsp;preserveFileDate)</code> <p>Copies a filtered directory to a new location.</p> </td> 
  </tr> 
  <tr> 
   <td><code>static void</code></td> 
   <td><code><a href="http://commons.apache.org/proper/commons-io/apidocs/org/apache/commons/io/FileUtils.html#copyDirectoryToDirectory-java.io.File-java.io.File-" rel="nofollow">copyDirectoryToDirectory</a>(<a href="http://docs.oracle.com/javase/7/docs/api/java/io/File.html?is-external=true" rel="nofollow">File</a>&nbsp;srcDir,&nbsp;<a href="http://docs.oracle.com/javase/7/docs/api/java/io/File.html?is-external=true" rel="nofollow">File</a>&nbsp;destDir)</code> <p>Copies a directory to within another directory preserving the file dates.</p> </td> 
  </tr> 
 </tbody> 
</table>

**1）将整个目录拷贝到新位置，并保持原文件日期：**`copyDirectory(File srcDir, File destDir)`

其包含文件及子目录文件并保持原文件日期

File file = new File("E:\\java\\file01");
    		String destFilePath = "E:\\java\\file03";
    		try {
    			//将整个目录复制新位置，并保持原文件日期。
    			FileUtils.copyDirectory(file, new File(destFilePath));
    			System.out.println("文件目录拷贝成功");
    		} catch (IOException e) {
    			e.printStackTrace();
    			System.out.println(e.getMessage());
    		}

![70 1][]

**2）将已筛选的目录拷贝的新位置：**`copyDirectory(File srcDir, File destDir, FileFilter filter)`

文件过滤器筛选 其包含文件及子目录文件 拷贝，并保持原文件日期。

String destFilePath = "E:\\java\\file04";
    //将已筛选的目录复制，并保持原文件日期的新位置。
    FileUtils.copyDirectory(file, new File(destFilePath), new FileFilter() {
    	@Override
    	public boolean accept(File pathname) {
    		if(pathname.isDirectory()) return true;
    		else {
    			boolean b1 = pathname.getName().endsWith(".txt");
    			boolean b2 = pathname.getName().endsWith(".jpg");
    			return b1 || b2;
    		}
    	}
    });

![70 2][]

### 三、删除目录及文件 ###

<table> 
 <tbody> 
  <tr> 
   <td><code>static void</code></td> 
   <td><code><a href="http://commons.apache.org/proper/commons-io/apidocs/org/apache/commons/io/FileUtils.html#deleteDirectory-java.io.File-" rel="nofollow">deleteDirectory</a>(<a href="http://docs.oracle.com/javase/7/docs/api/java/io/File.html?is-external=true" rel="nofollow">File</a>&nbsp;directory)</code> <p>Deletes a directory recursively.</p> </td> 
  </tr> 
  <tr> 
   <td><code>static boolean</code></td> 
   <td><code><a href="http://commons.apache.org/proper/commons-io/apidocs/org/apache/commons/io/FileUtils.html#deleteQuietly-java.io.File-" rel="nofollow">deleteQuietly</a>(<a href="http://docs.oracle.com/javase/7/docs/api/java/io/File.html?is-external=true" rel="nofollow">File</a>&nbsp;file)</code> <p>Deletes a file, never throwing an exception.</p> </td> 
  </tr> 
  <tr> 
   <td><code>static void</code></td> 
   <td><code><a href="http://commons.apache.org/proper/commons-io/apidocs/org/apache/commons/io/FileUtils.html#forceDelete-java.io.File-" rel="nofollow">forceDelete</a>(<a href="http://docs.oracle.com/javase/7/docs/api/java/io/File.html?is-external=true" rel="nofollow">File</a>&nbsp;file)</code> <p>Deletes a file.</p> </td> 
  </tr> 
 </tbody> 
</table>

**1）删除指定文件，从不引发异常：**`deleteQuietly(File file)`

File file = new File("E:\\java\\file04\\abc雪.jpg");
    //删除指定文件，从不引发异常。
    FileUtils.deleteQuietly(file);

**2）删除指定文件，不存在报异常：**`forceDelete(File file)`

File file = new File("E:\\java\\file04\\abc雪.jpg");
    		try {
    			FileUtils.forceDelete(file);
    			System.out.println("操作成功");
    		} catch (IOException e) {
    			e.printStackTrace();
    			System.out.println(e.getMessage());
    		}

**3）递归删除目录：**`deleteDirectory(File directory)`

`   删除`其包含文件及子目录文件

File file = new File("E:\\java\\file04\\abc雪.jpg");
    		//递归删除目录。
    		try {
    			FileUtils.deleteDirectory(new File(destFilePath));
    			System.out.println("操作成功");
    		} catch (IOException e) {
    			e.printStackTrace();
    			System.out.println(e.getMessage());
    		}

### 四、清除目录：`cleanDirectory(File directory)` ###

<table> 
 <tbody> 
  <tr> 
   <td><code>static void</code></td> 
   <td><code><a href="http://commons.apache.org/proper/commons-io/apidocs/org/apache/commons/io/FileUtils.html#cleanDirectory-java.io.File-" rel="nofollow">cleanDirectory</a>(<a href="http://docs.oracle.com/javase/7/docs/api/java/io/File.html?is-external=true" rel="nofollow">File</a>&nbsp;directory)</code> <p>Cleans a directory without deleting it.</p> </td> 
  </tr> 
 </tbody> 
</table>

清除该目录下的文件及子目录文件而不删除该目录文件夹。该目录不存在会报错

String destFilePath = "E:\\java\\file04";
    try {
    	FileUtils.cleanDirectory(new File(destFilePath));
    	System.out.println("操作成功");
    } catch (IOException e) {
    	e.printStackTrace();
    	System.out.println(e.getMessage());
    }

其他方法查看API文档

[http_commons.apache.org_proper_commons-io_download_io.cgi]: http://commons.apache.org/proper/commons-io/download_io.cgi
[http_commons.apache.org_proper_commons-io_apidocs_org_apache_commons_io_FileUtils.html]: http://commons.apache.org/proper/commons-io/apidocs/org/apache/commons/io/FileUtils.html
[watermark_type_ZmFuZ3poZW5naGVpdGk_shadow_10_text_aHR0cHM6Ly9ibG9nLmNzZG4ubmV0L3FxXzQyNDAyODU0_size_27_color_FFFFFF_t_70]: /images/20220504/4649a2a9e74e4e16a65da872a17dad84.png
[70]: /images/20220504/6785a67aca124875baf201331e04e740.png
[70 1]: /images/20220504/4209bbf174e94b108018b4c80f726513.png
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