第十篇 IO流技术（十）

package com.zzp.commons;

import java.io.File;

import org.apache.commons.io.FileUtils;

/**
 *
 *  大小
 * @author java
 *
 */
public class CIOTest01 {
    public static void main(String[] args) {
        //文件的大小
        long len = FileUtils.sizeOf(new File("src/com/zzp/commons/CIOTest01.java"));
        System.out.println(len);
        //目录的大小
        len = FileUtils.sizeOf(new File("F:/workspace1/IO_Day04/"));
        System.out.println(len);
    }
}

package com.zzp.commons;

import java.io.File;
import java.util.Collection;

import org.apache.commons.io.FileUtils;
import org.apache.commons.io.filefilter.DirectoryFileFilter;
import org.apache.commons.io.filefilter.EmptyFileFilter;
import org.apache.commons.io.filefilter.FileFilterUtils;
import org.apache.commons.io.filefilter.SuffixFileFilter;

/**
 *
 *  列出子孙级
 * @author java
 *
 */
public class CIOTest02 {
    public static void main(String[] args) {
        Collection<File> listFiles = FileUtils.listFiles(new File("F:/workspace1/IO_Day04"),
                EmptyFileFilter.NOT_EMPTY, null);
        for (File file : listFiles) {
            System.out.println(file.getAbsolutePath());
        }
        System.out.println("===============================");

        listFiles = FileUtils.listFiles(new File("F:/workspace1/IO_Day04"),
                EmptyFileFilter.NOT_EMPTY, DirectoryFileFilter.INSTANCE);
        for (File file : listFiles) {
            System.out.println(file.getAbsolutePath());
        }
        System.out.println("===============================");

        listFiles = FileUtils.listFiles(new File("F:/workspace1/IO_Day04"),
                new SuffixFileFilter("java"), DirectoryFileFilter.INSTANCE);
        for (File file : listFiles) {
            System.out.println(file.getAbsolutePath());
        }
        System.out.println("===============================");

        listFiles = FileUtils.listFiles(new File("F:/workspace1/IO_Day04"),
                FileFilterUtils.or(new SuffixFileFilter("java"),
                        new SuffixFileFilter("class"),EmptyFileFilter.EMPTY), DirectoryFileFilter.INSTANCE);
        for (File file : listFiles) {
            System.out.println(file.getAbsolutePath());
        }
        System.out.println("===============================");

        listFiles = FileUtils.listFiles(new File("F:/workspace1/IO_Day04"),
                FileFilterUtils.and(new SuffixFileFilter("java"),
                        EmptyFileFilter.NOT_EMPTY), DirectoryFileFilter.INSTANCE);
        for (File file : listFiles) {
            System.out.println(file.getAbsolutePath());
        }
        System.out.println("===============================");
    }
}

package com.zzp.commons;

import java.io.File;
import java.io.IOException;
import java.util.Collection;
import java.util.List;

import org.apache.commons.io.FileUtils;
import org.apache.commons.io.LineIterator;
import org.apache.commons.io.filefilter.DirectoryFileFilter;
import org.apache.commons.io.filefilter.EmptyFileFilter;
import org.apache.commons.io.filefilter.FileFilterUtils;
import org.apache.commons.io.filefilter.SuffixFileFilter;

/**
 *
 * 读取内容
 * @author java
 *
 */
public class CIOTest03 {
    public static void main(String[] args) throws IOException {
        //读取文件
        String readFileToString = FileUtils.readFileToString(new File("1.txt"), "gbk");
        System.out.println(readFileToString);

        //读取成字节数组
        byte[] readFileToByteArray = FileUtils.readFileToByteArray(new File("1.txt"));
        System.out.println(readFileToByteArray.length);

        //逐行读取
        List<String> readLines = FileUtils.readLines(new File("1.txt"), "gbk");
        for (String string : readLines) {
            System.out.println(string);
        }

        LineIterator lineIterator = FileUtils.lineIterator(new File("1.txt"), "gbk");
        while(lineIterator.hasNext()){
            System.out.println(lineIterator.next());
        }
    }
}

package com.zzp.commons;

import java.io.File;
import java.io.IOException;
import java.util.ArrayList;
import java.util.Collection;
import java.util.List;

import org.apache.commons.io.FileUtils;
import org.apache.commons.io.LineIterator;
import org.apache.commons.io.filefilter.DirectoryFileFilter;
import org.apache.commons.io.filefilter.EmptyFileFilter;
import org.apache.commons.io.filefilter.FileFilterUtils;
import org.apache.commons.io.filefilter.SuffixFileFilter;

/**
 *
 * 写出内容
 * @author java
 *
 */
public class CIOTest04 {
    public static void main(String[] args) throws IOException {
        FileUtils.write(new File("2.txt"), "生活不易，且行且珍惜\r\n","gbk");
        FileUtils.writeStringToFile(new File("2.txt"), "是真的\r\n", "gbk",true);
        //写出列表
        List<String> datas =new ArrayList<String>();
        datas.add("张三");
        datas.add("李四");
        datas.add("王五");
        FileUtils.writeLines(new File("2.txt"), datas, "......", true);
    }
}

package com.zzp.commons;

import java.io.File;
import java.io.IOException;
import java.net.URL;
import java.util.ArrayList;
import java.util.Collection;
import java.util.List;

import org.apache.commons.io.FileUtils;
import org.apache.commons.io.IOUtils;
import org.apache.commons.io.LineIterator;
import org.apache.commons.io.filefilter.DirectoryFileFilter;
import org.apache.commons.io.filefilter.EmptyFileFilter;
import org.apache.commons.io.filefilter.FileFilterUtils;
import org.apache.commons.io.filefilter.SuffixFileFilter;

/**
 *
 * 拷贝
 * @author java
 *
 */
public class CIOTest05 {
    public static void main(String[] args) throws IOException {
        //复制文件
        /*FileUtils.copyFile(new File("1.txt"), new File("3.txt"));*/
        //复制文件到目录
        /*FileUtils.copyFileToDirectory(new File("1.txt"), new File("lib"));*/
        //复制目录到目录
        //FileUtils.copyDirectoryToDirectory(new File("lib"), new File("lib2"));
        //复制目录
        //FileUtils.copyDirectory(new File("lib"), new File("lib2"));
        //拷贝url内容
        /*String url = "https://pic2.zhimg.com/v2-7d01cab20858648cbf62333a7988e6d0_qhd.jpg";
        FileUtils.copyURLToFile(new URL(url), new File("marvel.jpg"));*/

        String string = IOUtils.toString(new URL("http://www.163.com"),"GBK");
        System.out.println(string);
    }
}

原文地址：https://www.cnblogs.com/zhangzhipeng001/p/9589399.html