commons IO examples

package simple.io;

import java.io.BufferedReader;
import java.io.File;
import java.io.IOException;
import java.io.InputStream;
import java.io.InputStreamReader;
import java.net.MalformedURLException;
import java.net.URL;
import java.util.List;

import org.apache.commons.io.FileSystemUtils;
import org.apache.commons.io.FileUtils;
import org.apache.commons.io.FilenameUtils;
import org.apache.commons.io.IOUtils;
import org.apache.commons.io.LineIterator;
import org.apache.commons.io.filefilter.AndFileFilter;
import org.apache.commons.io.filefilter.DirectoryFileFilter;
import org.apache.commons.io.filefilter.FileFilterUtils;
import org.apache.commons.io.filefilter.NotFileFilter;
import org.apache.commons.io.filefilter.OrFileFilter;
import org.apache.commons.io.filefilter.PrefixFileFilter;
import org.apache.commons.io.filefilter.SuffixFileFilter;
import org.junit.Test;

public class ApacheIO {

        /**
         * 用普通的Java IO来解析HTML <br>
         */
        @Test
        public void testReadURL1() throws MalformedURLException, IOException{
               
                 InputStream in = new URL( "http://www.blogjava.net/rongxh7" ).openStream();
                 try {
                   InputStreamReader inR = new InputStreamReader( in );
                   BufferedReader buf = new BufferedReader( inR );
                   String line;
                   while ( ( line = buf.readLine() ) != null ) {
                     System.out.println( line );
                   }
                 } finally {
                   in.close();
                 }
                   
        }
       
        /**
         * 用Apache IO来解析HTML <br>
         * 学习要点: <br>
         * IOUtils contains utility methods dealing with reading, writing and copying. <br>
         * The methods work on InputStream, OutputStream, Reader and Writer.
         */
        @Test
        public void testReadURL2() throws MalformedURLException, IOException {
                InputStream in = new URL("http://www.blogjava.net/rongxh7").openStream();
                try {
                        System.out.println(IOUtils.toString(in));
                } finally {
                        IOUtils.closeQuietly(in);
                }
        }
       
        /**
         * 用Apache IO来读文件<br>
         * 学习要点:<br>
         * The FileUtils class contains utility methods for working with File objects.<br>
         * These include reading, writing, copying and comparing files.
         */
        @Test
        public void testReadFile() throws IOException {
                File file = new File("README");
                List<String> lines = FileUtils.readLines(file, "GBK");
                for(String line : lines){
                        System.out.println(line);
                }
        }
       
        /**
         * 用Apache IO来操作文件名
         * The FilenameUtils class contains utility methods <br>
         * for working with filenames without using File objects.
         */
        @Test
        public void testFileName() {
                String filename = "C:/a/b/ccc.txt";
                String baseName = FilenameUtils.getBaseName(filename);  //ccc
                String extName = FilenameUtils.getExtension(filename);  //txt
                String fullPath = FilenameUtils.getFullPath(filename);  //C:/a/b
                String name = FilenameUtils.getName(filename);                  //ccc.txt
                System.out.println(baseName);
                System.out.println(extName);
                System.out.println(fullPath);
                System.out.println(name);
               
        }
       
        /**
         * 用Apache IO查询磁盘空间
         * The FileSystemUtils class contains utility methods <br>
         * for working with the file system to access functionality not supported by the JDK.
         */
        @Test
        public void testFindDrive() throws IOException{
                long space = FileSystemUtils.freeSpaceKb("C:/");        //查C盘还剩下多少可用空间
                System.out.println("C盘可用空间为: " + space/1024 + " MB");
        }
       
        /**
         * Line Iterator的用法 <br>
         * The org.apache.commons.io.LineIterator class provides a flexible way <br>
         * for working with a line-based file. An instance can be created directly, <br>
         * or via factory methods on FileUtils or IOUtils.
         */
        @Test
        public void testLineIterater() throws IOException{
                File file = new File("README");
                LineIterator it = FileUtils.lineIterator(file, "GBK");
                try{
                        while(it.hasNext()){
                                String line = it.nextLine();
                                System.out.println(line);
                        }
                } finally {
                        LineIterator.closeQuietly(it);
                }

        }
       
        /**
         *
         * 各种常用的FileFiter
         *
         * There are a number of 'primitive' filters:
     *
         * DirectoryFilter Only accept directories
         * PrefixFileFilter Filter based on a prefix
         * SuffixFileFilter Filter based on a suffix
         * NameFileFilter Filter based on a filename
         * WildcardFileFilter Filter based on wildcards
         * AgeFileFilter Filter based on last modified time of file
         * SizeFileFilter Filter based on file size
         *
         * And there are five 'boolean' filters:
         *
         * TrueFileFilter Accept all files
         * FalseFileFilter Accept no files
         * NotFileFilter Applies a logical NOT to an existing filter
         * AndFileFilter Combines two filters using a logical AND
         * OrFileFilter Combines two filter using a logical OR
         *
         */
       
        /**
         * FileFilter的用法1
         * 用 "new 子类" 的方式
         *
         */
        @Test
        public void testFileFilter1(){
                  File dir = new File("data");  //若表示本目录,则用"."
                  //Returns an array of strings naming the files and directories in the directory denoted by this abstract pathname that satisfy the specified filter.
                  String[] files = dir.list(
                        //Constructs a new file filter that ANDs the result of two other filters.
                    new AndFileFilter(
                   
                      new AndFileFilter(
                        new PrefixFileFilter("t"),      //Constructs a new Prefix file filter for a single prefix.
                        new OrFileFilter(       //Constructs a new file filter that ORs the result of two other filters.
                          new SuffixFileFilter(".txt"), //Constructs a new Suffix file filter for a single extension.
                          new SuffixFileFilter(".dic")
                        )
                      ),
                      //Constructs a new file filter that NOTs the result of another filters.
                      new NotFileFilter(
                        DirectoryFileFilter.INSTANCE    //This filter accepts Files that are directories.
                      )
                     
                    )
                  );
                  for ( int i=0; i<files.length; i++ ) {
                    System.out.println(files[i]);
                  }
        }
       
        /**
         * FileFilter的用法2
         * 用FileFilterUtils的方式
         */
        @Test
        public void testFileFilter2(){
                File dir = new File("data");
                  String[] files = dir.list(
                    FileFilterUtils.andFileFilter(
                      FileFilterUtils.andFileFilter(
                        FileFilterUtils.prefixFileFilter("t"),
                        FileFilterUtils.orFileFilter(
                          FileFilterUtils.suffixFileFilter(".txt"),
                          FileFilterUtils.suffixFileFilter(".dic")
                        )
                      ),
                      FileFilterUtils.notFileFilter(
                        FileFilterUtils.directoryFileFilter()
                      )
                    )
                  );
                  for ( int i=0; i<files.length; i++ ) {
                    System.out.println(files[i]);
                  }


        }
       
       
}