怎样用程序限制用户只能用浏览器来下载东西__sourceFilePathName_String_contentType_m_contentDisposition_file_

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怎样用程序限制用户只能用浏览器来下载东西

来源: 互联网发布时间：2015-05-13

本文导语: 我开始是用http报头来判断，但是蚂蚁、Flashget这些东西可以更改http报头。怎样限制用户只能用浏览器，或者是限制他们用单线程也可以，我想用程序来实现怎么办 | package com.shaosi.leon; import...

我开始是用http报头来判断，但是蚂蚁、Flashget这些东西可以更改http报头。怎样限制用户只能用浏览器，或者是限制他们用单线程也可以，我想用程序来实现怎么办

package com.shaosi.leon;

import java.io.*;
import java.util.Vector;
import javax.servlet.*;
import javax.servlet.http.*;
import javax.servlet.jsp.JspWriter;
import javax.servlet.jsp.PageContext;

/**
* The object which perfoms the download.
* @author: Leon Zhao
*/
public class Download {
    protected ServletContext m_application;
    protected HttpServletRequest m_request;
    protected HttpServletResponse m_response;
    private boolean m_denyPhysicalPath;
    private boolean m_forcePhysicalPath;
    private String m_contentDisposition;
    private Vector m_deniedFilesList;
    private Vector m_allowedFilesList;
    /**
     * save in a virtual if it exists else consider the path as a physical if the porperty denyPhysicalPath is false.
     */
    public static final int SAVE_AUTO = 0;
    /**
     * save the file only if the path is a virtual path.
     */
    public static final int SAVE_VIRTUAL = 1;
    /**
     * save the file only if the path is a physical path.
     */
    public static final int SAVE_PHYSICAL = 2;
    /**
     * open the file only if the path is a physical path.
     */
    /**
     * Download constructor comment.
     */
    public Download() {
        m_deniedFilesList = new Vector();
        m_allowedFilesList = new Vector();
        m_denyPhysicalPath = false;
        m_forcePhysicalPath = false;
        m_contentDisposition = new String();
    }
    /**
     * Downloads a file.
     * @param sourceFilePathName java.lang.String The full path to the file to download.
     * @exception UploadException
     * @exception IOException
     * @exception ServletException
     */
    public void downloadFile(String sourceFilePathName)
        throws UploadException, IOException, ServletException {
        downloadFile(sourceFilePathName, null, null);
    }
    /**
     * Downloads a file.
     * @param sourceFilePathName java.lang.String The full path to the file to download.
     * @param contentType java.lang.String the content type.
     * @exception UploadException
     * @exception IOException
     * @exception ServletException
     */
    public void downloadFile(String sourceFilePathName, String contentType)
        throws UploadException, IOException, ServletException {
        downloadFile(sourceFilePathName, contentType, null);
    }
    /**
     * Downloads a file.
     * @param sourceFilePathName java.lang.String The full path to the file to download.
     * @param contentType java.lang.String the content type.
     * @param destFileName java.lang.String the suggested file name.
     * @exception UploadException
     * @exception IOException
     * @exception ServletException
     */
    public void downloadFile(
        String sourceFilePathName,
        String contentType,
        String destFileName)
        throws UploadException, IOException, ServletException {
        downloadFile(sourceFilePathName, contentType, destFileName, 65000);
    }
    /**
     * Downloads a file.
     * @param sourceFilePathName java.lang.String The full path to the file to download.
     * @param contentType java.lang.String the content type.
     * @param destFileName java.lang.String the suggested file name.
     * @param blockSize int block size
     */
    public void downloadFile(
        String sourceFilePathName,
        String contentType,
        String destFileName,
        int blockSize)
        throws UploadException, IOException, ServletException {
        if (sourceFilePathName == null)
            throw new IllegalArgumentException(
                String.valueOf(
                    (new StringBuffer("File '")).append(sourceFilePathName).append(
                        "' not found (1040).")));
        if (sourceFilePathName.equals(""))
            throw new IllegalArgumentException(
                String.valueOf(
                    (new StringBuffer("File '")).append(sourceFilePathName).append(
                        "' not found (1040).")));
        if (!isVirtual(sourceFilePathName) && m_denyPhysicalPath)
            throw new SecurityException("Physical path is denied (1035).");
        if (isVirtual(sourceFilePathName))
            sourceFilePathName = m_application.getRealPath(sourceFilePathName);
        java.io.File file = new java.io.File(sourceFilePathName);
        FileInputStream fileIn = new FileInputStream(file);
        long fileLen = file.length();
        int readBytes = 0;
        int totalRead = 0;
        byte b[] = new byte[blockSize];
        if (contentType == null)
            m_response.setContentType("application/x-filler");
        else if (contentType.length() == 0)
            m_response.setContentType("application/x-filler");
        else
            m_response.setContentType(contentType);
        m_response.setContentLength((int) fileLen);
        m_contentDisposition =
            m_contentDisposition != null ? m_contentDisposition : "attachment;";
        if (destFileName == null)
            m_response.setHeader(
                "Content-Disposition",
                String.valueOf(
                    (new StringBuffer(String.valueOf(m_contentDisposition)))
                        .append(" filename=")
                        .append(getFileName(sourceFilePathName))));
        else if (destFileName.length() == 0)
            m_response.setHeader("Content-Disposition", m_contentDisposition);
        else
            m_response.setHeader(
                "Content-Disposition",
                String.valueOf(
                    (new StringBuffer(String.valueOf(m_contentDisposition)))
                        .append(" filename=")
                        .append(destFileName)));
        while ((long) totalRead