java io 文件

1,文件过滤器:
 

public class MyFileFilter {
//不能传参
	public static void main(String[] args) {
	    File dir = new File("c:/zhanghy");
	    File[] currentFiles = dir.listFiles(new MyFilter());
	    System.out.println(Arrays.toString(currentFiles));
	    
    }
}
class MyFilter implements FileFilter{
	//当前的文件跟文件进行比较,如果返回true,则表示符合要求
    public boolean accept(File pathname) {
	    return true;
    }
}

结果:
[c:\zhanghy\New Folder\BooleanConverter.java, c:\zhanghy\New Folder\CORAIL_REG_zhanghouyin .xls, c:\zhanghy\New Folder\CORV1P_PIL_IHM-CAP-T0800.xls, c:\zhanghy\New Folder\CORV1P_PIL_IHM-REF-11.xls, c:\zhanghy\New Folder\DateConverter.java, c:\zhanghy\New Folder\e371575_Timesheet.xls, c:\zhanghy\New Folder\ECW.doc, c:\zhanghy\New Folder\KO1QT01.txt]

public class MyFileFilter {
	public static void main(String[] args) {
	    File dir = new File("c:/zhanghy/New Folder");
	    File[] currentFiles = dir.listFiles(new MyFilter());
	    System.out.println(Arrays.toString(currentFiles));
	    
    }
}
class MyFilter implements FileFilter{
	//取得所有java文件，（判断当前文件是.java结尾）
    public boolean accept(File pathname) {
	    if(pathname.getName() != null && pathname.getName().endsWith(".java")){
	    	return true;
	    }
    	return false;
    }
}

结果:
[c:\zhanghy\New Folder\BooleanConverter.java, c:\zhanghy\New Folder\DateConverter.java]

public class MyFileFilter {
//可以传参
	public static void main(String[] args) {
	    File dir = new File("c:/zhanghy/New Folder");
	    //取得所有.java文件
	    File[] currentFiles = dir.listFiles(new YourFilter(".java"));
	    System.out.println(Arrays.toString(currentFiles));
	    
    }
}
class YourFilter implements FileFilter{
	private String requestFile;//过滤条件
	public YourFilter(String requestFile){
    	this.requestFile = requestFile;
    }
    public boolean accept(File pathname) {
	    if(pathname.getName() != null && pathname.getName().endsWith(requestFile)){
	    	return true;
	    }
    	return false;
    }
}

结果为:
[c:\zhanghy\New Folder\BooleanConverter.java, c:\zhanghy\New Folder\DateConverter.java]

public class MyFileFilter {
//不能传参
	private static FileFilter myFilter = new FileFilter() {
		public boolean accept(File pathname) {
			if(pathname.getName() != null && pathname.getName().endsWith(".java"))
				return true;
			return false;
		}
	};
	public static void main(String[] args) {
	    File dir = new File("c:/zhanghy/New Folder");
	    //取得所有.java文件
	    File[] currentFiles = dir.listFiles(myFilter);
	    System.out.println(Arrays.toString(currentFiles));
    }
}

结果:
[c:\zhanghy\New Folder\BooleanConverter.java, c:\zhanghy\New Folder\DateConverter.java]