前言:
文件IO是程序设计语言的一个特点,本文将针对Java的File文件名过滤进行测试。
测试目录截图:
测试结果:
data.txt
output-3.txt
output-4.txt
output-d.txt
people-id.txt
qqmusic_cn_seed.txt
text-a20.txt
--- finish ----
版本一:接口继承
package com.yeezhao.common.io.v1;
import java.io.File;
import java.io.FilenameFilter;
import java.util.regex.Pattern;
public class MyFilenameFilter implements FilenameFilter {
final static String REGEX = ".*\\.txt";
@Override
public boolean accept(File dir, String name) {
return Pattern.matches(REGEX, name);
}
}
package com.yeezhao.common.io.v1;
import java.io.File;
import java.util.Arrays;
public class FilenameFilterV1 {
public static void main(String[] args) throws Exception{
System.out.println("--- start ----");
File file = new File("c://test");
String[] list = file.list(new MyFilenameFilter());
Arrays.sort(list, String.CASE_INSENSITIVE_ORDER); //忽略字符串大小写进行字典排序
for(String l:list){
System.out.println(l);
}
System.out.println("--- finish ----");
}
}
版本二:内部类初始化内部对象属性
package com.yeezhao.common.io.v2;
import java.io.File;
import java.io.FilenameFilter;
import java.util.Arrays;
import java.util.regex.Pattern;
public class FilenameFilterV2 {
private static String REGEX =".*\\.txt";
private static FilenameFilter filter = new FilenameFilter() {
@Override
public boolean accept(File dir, String name) {
return Pattern.matches(REGEX, name);
}
};
public static void main(String[] args) throws Exception {
File file = new File("c://test");
String[] list = file.list(filter);
Arrays.sort(list, String.CASE_INSENSITIVE_ORDER); //忽略字符串大小写进行字典排序
for (String l : list) {
System.out.println(l);
}
System.out.println("--- finish ----");
}
}
版本三:内部类直接调用方法
package com.yeezhao.common.io.v3;
import java.io.File;
import java.io.FilenameFilter;
import java.util.Arrays;
import java.util.regex.Pattern;
public class FilenameFilterV3 {
private static String REGEX =".*\\.txt";
public static void main(String[] args) {
File file = new File("c://test/");
String[] list = file.list(new FilenameFilter() {
@Override
public boolean accept(File dir, String name) {
return Pattern.matches(REGEX, name);
}
});
Arrays.sort(list, String.CASE_INSENSITIVE_ORDER); //忽略字符串大小写进行字典排序
for (String l : list) {
System.out.println(l);
}
System.out.println("--- finish ----");
}
}
附:File对象的list()方法
后语:
Java.io涉及相当多的工具类,后续在研究之余希望能上手java.nio的一些内容并进行对比为是!