import java.io.*;
import java.util.*;

import com.jcraft.jsch.Channel;
import com.jcraft.jsch.ChannelSftp;
import com.jcraft.jsch.ChannelSftp.LsEntry;
import com.jcraft.jsch.JSch;
import com.jcraft.jsch.Session;

public class SftpClientUtil {

    /**
     * Sftp
     */
    ChannelSftp sftp = null;
    /**
     * 主机
     */
    private String host = "";
    /**
     * 端口
     */
    private int port = 0;
    /**
     * 用户名
     */
    private String username = "";
    /**
     * 密码
     */
    private String password = "";

    /**
     * 构造函数
     *
     * @param host     主机
     * @param port     端口
     * @param username 用户名
     * @param password 密码
     */
    public SftpClientUtil(String host, int port, String username,String password) {
        this.host = host;
        this.port = port;
        this.username = username;
        this.password = password;
    }

    /**
     * 连接sftp服务器
     *
     * @throws Exception
     */
    public void connect() throws Exception {

        JSch jsch = new JSch();
        Session sshSession = jsch.getSession(this.username, this.host);

        sshSession.setPassword(password);
        Properties sshConfig = new Properties();
        sshConfig.put("StrictHostKeyChecking", "no");
        sshSession.setConfig(sshConfig);
        sshSession.connect();
        Channel channel = sshSession.openChannel("sftp");
        channel.connect();
        this.sftp = (ChannelSftp) channel;
    }

    /**
     * 关闭连接
     *
     * @throws Exception
     */
    public void disconnect() throws Exception {
        if (this.sftp != null) {
            if (this.sftp.isConnected()) {
                this.sftp.disconnect();
            } else if (this.sftp.isClosed()) {

            }
        }
    }

    /**
     * 上传单个文件
     *
     * @param directory  上传的目录
     * @param uploadFile 要上传的文件
     * @throws Exception
     */
    public void upload(String directory, String uploadFile) throws Exception {
        this.sftp.cd(directory);
        File file = new File(uploadFile);
        this.sftp.put(new FileInputStream(file), file.getName());
    }

    /**
     * 上传目录下全部文件
     *
     * @param directory 上传的目录
     * @throws Exception
     */
    public void uploadByDirectory(String directory) throws Exception {

        String uploadFile = "";
        List<String> uploadFileList = this.listFiles(directory);
        Iterator<String> it = uploadFileList.iterator();

        while (it.hasNext()) {
            uploadFile = it.next().toString();
            this.upload(directory, uploadFile);
        }
    }

    /**
     * 下载单个文件
     *
     * @param directory     下载目录
     * @param downloadFile  下载的文件
     * @param saveDirectory 存在本地的路径
     * @throws Exception
     */
    public void download(String directory, String downloadFile, String saveDirectory) throws Exception {
        String saveFile = saveDirectory + "//" + downloadFile;

        this.sftp.cd(directory);
        File file = new File(saveFile);
        this.sftp.get(downloadFile, new FileOutputStream(file));
    }

    /**
     * 下载目录下全部文件
     *
     * @param directory     下载目录
     * @param saveDirectory 存在本地的路径
     * @throws Exception
     */
    public void downloadByDirectory(String directory, String saveDirectory) throws Exception {
        String downloadFile = "";
        List<String> downloadFileList = this.listFiles(directory);
        Iterator<String> it = downloadFileList.iterator();

        while (it.hasNext()) {
            downloadFile = it.next().toString();
            if (downloadFile.toString().indexOf(".") < 0) {
                continue;
            }
            this.download(directory, downloadFile, saveDirectory);
        }
    }

    /**
     * 删除文件
     *
     * @param directory  要删除文件所在目录
     * @param deleteFile 要删除的文件
     * @throws Exception
     */
    public void delete(String directory, String deleteFile) throws Exception {
        this.sftp.cd(directory);
        this.sftp.rm(deleteFile);
    }

    /**
     * 列出目录下的文件
     *
     * @param directory 要列出的目录
     * @return list 文件名列表
     * @throws Exception
     */
    @SuppressWarnings("unchecked")
    public List<String> listFiles(String directory) throws Exception {

        Vector fileList;
        List<String> fileNameList = new ArrayList<String>();

        fileList = this.sftp.ls(directory);
        Iterator it = fileList.iterator();

        while (it.hasNext()) {
            String fileName = ((LsEntry) it.next()).getFilename();
            if (".".equals(fileName) || "..".equals(fileName)) {
                continue;
            }
            fileNameList.add(fileName);

        }

        return fileNameList;
    }

    /**
     * 更改文件名
     *
     * @param directory 文件所在目录
     * @param oldFileNm 原文件名
     * @param newFileNm 新文件名
     * @throws Exception
     */
    public void rename(String directory, String oldFileNm, String newFileNm) throws Exception {
        this.sftp.cd(directory);
        this.sftp.rename(oldFileNm, newFileNm);
    }

    public void cd(String directory) throws Exception {
        this.sftp.cd(directory);
    }

    public InputStream get(String directory) throws Exception {
        InputStream streatm = this.sftp.get(directory);
        return streatm;
    }

}