java的File類的兩個小例子

Java的File類在Java的java.io包下，代表與平臺無關的目錄，下面是幾個小例子開說明他，具體的細節翻看API就好了。。

public class Ha {

    public static void main(String[] args)
    {
        File file= new  File("D:\\ha");
        System.out.println(file.getName());
        System.out.println(file.getParent());
        System.out.println(file.getAbsoluteFile());
        System.out.println(file.getAbsoluteFile().getParent());
        try {
            File temFile =  File.createTempFile("aaa",".txt",file);
            temFile.deleteOnExit();
        } catch (IOException e) {
            e.printStackTrace();  //To change body of catch statement use File | Settings | File Templates.
        }
        File newFile = new File(System.currentTimeMillis()+"");
        System.out.println("newFiel對象是否存在："+newFile.exists());
        try {
            newFile.createNewFile();
            newFile.mkdir();

        } catch (IOException e) {
            e.printStackTrace();  //To change body of catch statement use File | Settings | File Templates.
        }
        String[] fileList = file.list();
        System.out.println("當前路徑下所有文件和路徑如下："+"\n");
        for(String str:fileList)
        {
            System.out.println(str);
        }
        File[] roots = File.listRoots();
        System.out.println("系統所有根目錄如下：");
        for(File root:roots)
        {
            System.out.println(root);
        }
    }
}

上面這個是最基本的操作。。。

下面是對一種文件的過濾的例子：

public class FileTest {

    public static void main(String[] args)
    {
        File file = new File("D:\\ha");
        String[] nameList = file.list(new MyFilter());
        for(String str:nameList)
        {
            System.out.println(str);
        }
    }
}

class MyFilter implements FilenameFilter
{
    public boolean accept(File fl,String name)
    {
        return name.endsWith(".java")||new File(name).isDirectory();
    }
}

通過運行代碼來查看。。。