commons-io之FileUtils

淩亂°似流年 2021-12-09 04:15 213阅读 0赞

## 工具方法 ##

*  创建目录

> org.apache.commons.io.FileUtils\#forceMkdir(File directory)

*  写文件

> org.apache.commons.io.FileUtils\#write(java.io.File, java.lang.CharSequence, java.lang.String, boolean)

## 普通文件读写 ##

package com.io;
    
    import java.io.BufferedInputStream;
    import java.io.BufferedOutputStream;
    import java.io.File;
    import java.io.FileInputStream;
    import java.io.FileOutputStream;
    import java.nio.charset.Charset;
    
    /** * @author yanyugang * @description 文件读写例子 * @date 2019-10-14 9:36 */
    public class ReadWriteFile { 
        private static final String path="D:/readwritefile.txt";
    
        public static void main(String[] args){ 
            // 写文件
            writeFileFun();
            // 读文件
            readFileFun();
    
        }
    
        private static void writeFileFun(){ 
            //待写入的内容
            StringBuffer buf=new StringBuffer();
            buf.append("Hello World!").append("\r\n");
            buf.append("你好，世界！").append("\r\n");
            buf.append("Hello Java!").append("\r\n");
            buf.append("你好，Java！").append("\r\n");
    
            File file = new File(path);
            if (!file.exists()) { 
                file.getParentFile().mkdirs();
            }
    
            try (BufferedOutputStream bos=new BufferedOutputStream(new FileOutputStream(file, true))) { 
                // 父级目录存在的情况下，文件才能创建成功
                bos.write(buf.toString().getBytes(Charset.defaultCharset()));
                bos.flush();
            } catch (Exception e) { 
                e.printStackTrace();
            }
        }
    
        private static void readFileFun(){ 
            //待读取的内容
            try (BufferedInputStream bis=new BufferedInputStream(new FileInputStream(new File(path)))) { 
                byte[] buf=new byte[1024];
                int len=0;
                System.out.println("------------------读取内容--------------------------");
                while ((len=bis.read(buf))!=-1) { 
                    System.out.println(new String(buf, 0, len));
                }
            } catch (Exception e) { 
                e.printStackTrace();
            }
        }
    
    
    }

## commons-io文件读写 ##

package com.io;
    
    import org.apache.commons.io.FileUtils;
    
    import java.io.File;
    import java.io.IOException;
    
    /** * @author yanyugang * @description commons-io实现文件读写例子 * @date 2019-10-14 9:36 */
    public class CommonsIoReadWriteFile { 
        private static final String path="D:/day22/commonsioreadwritefile.txt";
    
        public static void main(String[] args){ 
            // 写文件
            writeFileFun();
            // 读文件
            readFileFun();
    
        }
    
        private static void writeFileFun(){ 
            //待写入的内容
            StringBuffer buf=new StringBuffer();
            buf.append("Hello World!").append("\r\n");
            buf.append("你好，世界！").append("\r\n");
            buf.append("Hello Java!").append("\r\n");
            buf.append("你好，Java！").append("\r\n");
            try { 
                FileUtils.writeStringToFile(new File(path), buf.toString(), "UTF-8", true);
            } catch (IOException e) { 
                e.printStackTrace();
            }
        }
    
        private static void readFileFun(){ 
            //待读取的内容
            System.out.println("------------------读取内容--------------------------");
            try { 
                System.out.println(FileUtils.readFileToString(new File(path), "UTF-8"));
            } catch (IOException e) { 
                e.printStackTrace();
            }
        }
    
    
    }