Java 从FTP下载.上传文件详解编程语言

<dependency> 
　　<groupId>commons-net</groupId> 
   <artifactId>commons-net</artifactId> 
   <version>3.1</version> 
</dependency>

package com.tools.ftp; 
 
import org.apache.commons.net.ftp.FTP; 
import org.apache.commons.net.ftp.FTPClient; 
import org.apache.commons.net.ftp.FTPReply; 
import org.springframework.beans.factory.annotation.Value; 
import org.springframework.stereotype.Component; 
import java.io.*; 
import java.net.SocketException; 
 
/** 
 * @author admin 
 * @title: FtpUtils 
 * @projectName tools 
 * @description: FTP工具类 
 * @date 2020/3/1913:23 
 */ 
@Component 
public class FtpUtils { 
 
    /**FTP IP*/ 
    @Value("${ftp.host}") 
    private String ftpHost; 
    /**FTP用户名*/ 
    @Value("${ftp.userName}") 
    private String ftpUserName; 
    /**FTP密码*/ 
    @Value("${ftp.password}") 
    private String ftpPassword; 
    /**FTP 端口 默认21*/ 
    @Value("${ftp.port}") 
    private int ftpPort =21; 
 
    public static final String CHARSET_GBK = "GBK"; 
 
    public static final String CHARSET_UTF8 = "UTF-8"; 
 
    public static final String CHARSET_ISO = "iso-8859-1"; 
 
    /** 
     * 获取FTPClient 
     * @return 
     */ 
    public  FTPClient getFTPClient() { 
        FTPClient ftpClient = new FTPClient(); 
        try { 
            ftpClient = new FTPClient(); 
            // 连接FTP服务器 
            ftpClient.connect(ftpHost, ftpPort); 
            // 登陆FTP服务器 
            ftpClient.login(ftpUserName, ftpPassword); 
            if (!FTPReply.isPositiveCompletion(ftpClient.getReplyCode())) { 
                System.out.println("未连接到FTP，用户名或密码错误。"); 
                ftpClient.disconnect(); 
            } else { 
                System.out.println("FTP连接成功。"); 
            } 
        } catch (SocketException e) { 
            e.printStackTrace(); 
            System.out.println("FTP的IP地址可能错误，请正确配置。"); 
        } catch (IOException e) { 
            e.printStackTrace(); 
            System.out.println("FTP的端口错误,请正确配置。"); 
        } 
        return ftpClient; 
    } 
 
    /** 
     * 下载文件 
     * @param ftpPath  ftp文件存放物理路径 
     * @param fileName 文件路径 
     */ 
    public  void downloadFile(String ftpPath, String localPath, String fileName) { 
        FTPClient ftpClient = null; 
        try { 
            ftpClient = getFTPClient(); 
            // 中文支持 
            ftpClient.setControlEncoding(CHARSET_UTF8); 
            ftpClient.setFileType(FTPClient.BINARY_FILE_TYPE); 
            ftpClient.enterLocalPassiveMode(); 
            ftpClient.changeWorkingDirectory(ftpPath); 
            File localFile = new File(localPath + File.separatorChar + fileName); 
            OutputStream os = new FileOutputStream(localFile); 
            ftpClient.retrieveFile(fileName, os); 
            os.close(); 
            ftpClient.logout(); 
        } catch (FileNotFoundException e) { 
            System.out.println("没有找到" + ftpPath + "文件"); 
            e.printStackTrace(); 
        } catch (SocketException e) { 
            System.out.println("连接FTP失败."); 
            e.printStackTrace(); 
        } catch (IOException e) { 
            e.printStackTrace(); 
            System.out.println("文件读取错误。"); 
            e.printStackTrace(); 
        } 
    } 
 
    /** 
     * 上传文件 
     * @param ftpPath  ftp文件存放物理路径 
     * @param fileName 文件路径 
     * @param input 文件输入流，即从本地服务器读取文件的IO输入流 
     */ 
    public  void uploadFile(String ftpPath,String fileName,InputStream input){ 
        FTPClient ftp=null; 
        try { 
            ftp=getFTPClient(); 
            ftp.changeWorkingDirectory(ftpPath); 
            ftp.setFileType(FTP.BINARY_FILE_TYPE); 
            fileName=new String(fileName.getBytes(CHARSET_GBK),CHARSET_ISO); 
            ftp.storeFile(fileName, input); 
            input.close(); 
            ftp.logout(); 
            System.out.println("upload succes!"); 
        } catch (Exception e) { 
            e.printStackTrace(); 
        } 
    } 
 
 
    public String getFtpHost() { 
        return ftpHost; 
    } 
 
    public void setFtpHost(String ftpHost) { 
        this.ftpHost = ftpHost; 
    } 
 
    public String getFtpUserName() { 
        return ftpUserName; 
    } 
 
    public void setFtpUserName(String ftpUserName) { 
        this.ftpUserName = ftpUserName; 
    } 
 
    public String getFtpPassword() { 
        return ftpPassword; 
    } 
 
    public void setFtpPassword(String ftpPassword) { 
        this.ftpPassword = ftpPassword; 
    } 
 
    public int getFtpPort() { 
        return ftpPort; 
    } 
 
    public void setFtpPort(int ftpPort) { 
        this.ftpPort = ftpPort; 
    } 
}