jspfiledownload.java

java jsp download code

package com.vogoal.util;

import java.io.BufferedInputStream;
import java.io.File;
import java.io.FileInputStream;
import java.io.FileOutputStream;
import java.io.IOException;
import java.io.InputStream;
import java.util.zip.ZipEntry;
import java.util.zip.ZipOutputStream;

import javax.servlet.http.HttpServletResponse;
/*
* vogoalAPI 1.0
* Auther [e-mail]
* by vogoal.com
* mail: [e-mail]
*/

/**
* JSP FILE DOWNLOAD SUPPORT
* 
* @author SinNeR
* @version 1.0
*/
public class JspFileDownload {
	/** request object */
	private HttpServletResponse response = null;

	/** file type: -1 un-setting; 0 normal file; 1 zip file ;2 stream*/
	private int fileType = -1;
	
	/** file name to be displayed */
	private String disFileName = null;
	
	/** zip file path */
	private String zipFilePath = null;
	
	/** file to be zipped */
	private String[] zipFileNames = null;
	
	private boolean zipDelFlag = false;
	
	/** file to be downloaded */
	private String downFileName = null;
	
	/** error code 0 */
	private static final int PROCESS_OK = 0;
	
	/** error code 1 */
	private static final int RESPONSE_IS_NULL = 1;
	
	/** error code 2 */
	private static final int UNSET_DOWNLOADTYPE = 2;
	
	/** error code 3 */
	private static final int UNSET_DIS_FILE_NAME = 3;
	
	/** error code 4 */
	private static final int UNSET_DOWN_FILE_NAME = 4;
	
	/** error code 9 */
	private static final int IO_EXCEPTION = 9;
	
	/**
	 * set response object
	 * @param response response Object
	 */
	public void setResponse(HttpServletResponse response){
		this.response = response;
	}
	
	/**
	 * set file type 0 normal file; 1 zip file ;2 stream
	 * @param fileType
	 */
	public void setDownType(int fileType){
		this.fileType = fileType;
	}
	
	/**
	 * set display file name
	 * @param fileName
	 */
	public void setDisFileName(String fileName){
		this.disFileName = fileName;
	}
	
	/**
	 * set zip file path
	 * @param fileNames
	 */
	public void setZipFilePath( String path ){
		this.zipFilePath = path;
	}
	
	public void setZipDelFlag(boolean b){
		this.zipDelFlag = b;
	}
	
	/**
	 * set zip file names
	 * @param fileNames
	 */
	public void setZipFileNames(String[] fileNames){
		this.zipFileNames = fileNames;
	}
	
	/**
	 * set download file name
	 * @param fileName
	 */
	public void setDownFileName(String fileName){
		this.downFileName = fileName;
	}
	
	/**
	 * set file content
	 * @param fileContent
	 */
	public int setFileContent(String fileContent){	
		try{	
			byte[] buffs = fileContent.getBytes("UTF-8");
			response.getOutputStream().write(buffs);
		}catch(IOException e){
			return IO_EXCEPTION;
		}
		return PROCESS_OK;
	}
	
	/**
	 * set file content
	 * @param fileContent
	 */
	public int setFileContent(byte[] fileContent){
		try{
			response.getOutputStream().write(fileContent);
		}catch(IOException e){
			return IO_EXCEPTION;
		}
		return PROCESS_OK;
	}
	
	/**
	 * set file content end
	 *
	 */
	public int setFileContentEnd(){
		try{
			response.getOutputStream().close();
		}catch(IOException e){
			return IO_EXCEPTION;
		}
		return PROCESS_OK;
	}
	
	/**
	 * main process
	 * @return
	 */
	public int process(){
		int status = PROCESS_OK;
		
		status = preCheck();
		if ( status != PROCESS_OK )
			return status;
			
		String fileName = disFileName;
		
		response.setContentType("APPLICATION/OCTET-STREAM");   
		response.setHeader("Content-Disposition","attachment;filename=\"" + fileName + "\"");
		int BUFSIZE = 1024 * 8;		
		int rtnPos = 0;
		byte[] buffs = new byte[ BUFSIZE ];
		FileInputStream inStream = null;
		ZipOutputStream zos = null;
		InputStream is = null;
		String filepath = null;
		try{
		  
			if ( fileType == 0 || fileType == 1){
				if ( fileType == 0 ){
					filepath = downFileName;   
				}else{
					filepath = zipFilePath + fileName;
					String[] fileToZip = zipFileNames;
									
					zos=new ZipOutputStream(new FileOutputStream(filepath));
					ZipEntry ze=null;
					byte[] buf=new byte[BUFSIZE];
					int readLen=0;
					for (int i= 0;i<fileToZip.length;i++){
						File f= new File(fileToZip[i]);
		
						ze=new ZipEntry(f.getName());
						ze.setSize(f.length());
						ze.setTime(f.lastModified());
		
						zos.putNextEntry(ze);
						is=new BufferedInputStream(new FileInputStream(f));
						while ((readLen=is.read(buf, 0, BUFSIZE))!=-1) {
							zos.write(buf, 0, readLen);
						}
						is.close();
					}
					zos.close();
				}
		   
				inStream =new FileInputStream(filepath);   
   
				while((rtnPos=inStream.read(buffs)) >0)   
					response.getOutputStream().write(buffs,0,rtnPos);   
				response.getOutputStream().close();   
				inStream.close();
			}
			if ( zipDelFlag ){
				File fToDel = new File(filepath);
				fToDel.delete();
			}

		}catch(IOException e){
			return IO_EXCEPTION;
		}finally{
			try{
				if ( inStream != null ){
					inStream.close();
					inStream = null;
				}
				if ( zos != null ){
					zos.close();
					zos = null;
				}
				if ( is != null ){
					is.close();
					is = null;
				}
			}catch (IOException e){
			}
		}
		return status;
	}
	
	/**
	 * pre check.
	 * @return
	 */
	private int preCheck(){
		
		if ( response == null )
			return RESPONSE_IS_NULL;
			
		if ( disFileName == null || disFileName.trim().length() == 0 )
			return UNSET_DIS_FILE_NAME;
		if ( fileType == -1 )
			return UNSET_DOWNLOADTYPE;
		else if ( fileType == 0 ){
			if ( downFileName == null || downFileName.trim().length() == 0 )
				return UNSET_DOWN_FILE_NAME;
			else{
				if ( !isFile( downFileName ) )
					return UNSET_DOWN_FILE_NAME;
			}
			
		}else if ( fileType == 1 ){
			if ( zipFilePath == null || zipFilePath.length() == 0 )
				return UNSET_DOWN_FILE_NAME;
			else{
				if ( !isDirect(zipFilePath) )
					return UNSET_DOWN_FILE_NAME;
			}
			if ( zipFileNames == null || zipFileNames.length == 0 )
				return UNSET_DOWN_FILE_NAME;
			else{
				for ( int i=0;i<zipFileNames.length;i++ ){
					if ( zipFileNames[i] == null || zipFileNames[i].trim().length() == 0 )
						return UNSET_DOWN_FILE_NAME;
					else{
						if ( !isFile( zipFileNames[i] ) )
							return UNSET_DOWN_FILE_NAME;
					}
				}
			}
		}else if ( fileType == 2 ){
			//doing nothing
		}else{
			return UNSET_DOWNLOADTYPE;
		}
		return PROCESS_OK;
	}
	
	private boolean isFile(String fileName){
		File f = new File(fileName);
		if (!f.exists() || !f.isFile())
			return false;
		return true;
	}
	
	private boolean isDirect(String filePath){
		File f = new File(filePath);
		if (!f.exists() || !f.isDirectory())
			return false;
		return true;
	}
}