分享一段归集同类型文件的代码

        解决的问题：一个超级庞大的文件加，里面有一些我们需要的文件， 把他们找出来。 具体自己看吧，用的上就拿去。

 

import java.io.File;
import java.io.FileInputStream;
import java.io.FileOutputStream;
import java.io.FileWriter;
import java.io.IOException;
import java.nio.channels.FileChannel;

import org.apache.commons.io.FileUtils;

/**
 * @author Stony Zhang  (zhangyu0182@sina.com)
 * http://mybeautiful.iteye.com
 */
public class BatchFileRename {
	private File targetFolder;
	private String soureFolder;
	private String extName; // such as ".png"
	private FileNameHander nameHandler;
	private FileWriter contentFileWriter;


	public BatchFileRename(String soureFolder, String targetFolder, String extName) {
		this(soureFolder,targetFolder,extName, true);
	}
	public BatchFileRename(String soureFolder, String targetFolder, String extName, boolean cleanTarget) {
		this.soureFolder = soureFolder;
		this.extName = extName;
		this.targetFolder = new File(targetFolder);
		if(!this.targetFolder.exists()){
			this.targetFolder.mkdirs();
		}
		
		if (cleanTarget){
			try {
				FileUtils.cleanDirectory(this.targetFolder);
			} catch (IOException e) {
				e.printStackTrace();
			}
		}
		
		try {
			contentFileWriter = new FileWriter(new File(targetFolder, "content.txt"), true);
		} catch (IOException e) {
			e.printStackTrace();
		}
	}

	public void execute() {
		File sourceDir = new File(this.soureFolder);
		if (!sourceDir.isDirectory()) {
			System.out.println("Pls specified an correct forder!");
			return;
		}
		scanFolder(sourceDir);

		try {
			contentFileWriter.close();
		} catch (IOException e) {
			e.printStackTrace();
		}
	}

	private void scanFolder(File sourceDir) {
		File[] list = sourceDir.listFiles();
		for (File file : list) {
			if (file.isDirectory()) {
				scanFolder(file);
				continue;
			}
			if (!file.getName().endsWith(extName)) {
				continue;
			}
			this.copyToTargetFolder(file);
		}
	}

	private void copyToTargetFolder(File file) {
		try {
			// check if the file exists?
			String fileName = this.getFileName(file);
			System.out.println("Copy file :" + file.getAbsolutePath());
			contentFileWriter.write(String.format("%-40s   %s\r\n", fileName, file.getAbsolutePath()));
			contentFileWriter.write(String.format("%80s\r\n", "_").replace(" ", "_"));
			copyFile(file, new File(this.targetFolder, fileName));
		} catch (IOException e) {
			e.printStackTrace();
		}

	}

	private String getFileName(File file) {
		String fName = getNameHandler().newName(file);
		File destFile = new File(this.targetFolder, fName);
		if (!destFile.exists()) {
			return fName;
		}
		String newFileName;
		int index = fName.lastIndexOf(".");
		if (index > 0) {
			String mainName = fName.substring(0, index);
			String extName = fName.substring(index);
			newFileName = mainName + "_1" + extName;
		} else {
			newFileName = fName + "_1";
		}
		File newFile = new File(this.targetFolder, newFileName);
		if (newFile.exists()) {
			return getFileName(newFile);
		}
		return newFileName;

	}

	public static void copyFile(File in, File out) throws IOException {
		FileInputStream fileInputStream = new FileInputStream(in);
		FileOutputStream fileOutputStream = new FileOutputStream(out);
		try {
			FileChannel sourceChannel = fileInputStream.getChannel();
			FileChannel destinationChannel = fileOutputStream.getChannel();
			sourceChannel.transferTo(0, sourceChannel.size(), destinationChannel);
			// or destinationChannel.transferFrom(sourceChannel, 0,
			// sourceChannel.size());
			fileInputStream.close();
			fileOutputStream.close();
			sourceChannel.close();
			destinationChannel.close();
		} catch (Exception e) {
			e.printStackTrace();
		} finally {

		}

	}

	public static void main(String[] args) {
		BatchFileRename run = new BatchFileRename("f:\\temp\\test_src", "F:\\temp\\test_dest", ".png");
		run.setNameHandler(new FileNameHander() {

			@Override
			public String newName(File file) {
				return file.getName().toLowerCase();
			}
		});
		run.execute();

	}

	public FileNameHander getNameHandler() {
		return nameHandler;
	}

	public void setNameHandler(FileNameHander nameHandler) {
		this.nameHandler = nameHandler;
	}

	private static interface FileNameHander {
		String newName(File file);
	}
}

 

  注意： 依赖common-io.