Java-从url获取文件信息，压缩并导出

本文主要用来从url获取文件输入流，并且将其加入zip的输出流并导出

环境
jfinal
tomcat
jdk1.7

jfinal并不是官网标准的框架。

目录

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1从url获取文件信息

文件1：GetFile.java
结构：

import java.io.IOException;import java.io.InputStream;import java.io.UnsupportedEncodingException;import java.net.MalformedURLException;import java.net.URL;import java.net.URLConnection;import java.util.List;import java.util.Map;import java.util.Set;public class GetFile {    //1.1从url获取文件的输入流    public InputStream getFileInputStream(String url) throws Exception{}    //1.2从url获取文件名    public String getFileName(String url) throws IOException{}}

1.1从url获取文件的输入流

public InputStream getFileInputStream(String url) throws Exception{        InputStream murl = new URL(url).openStream();        return murl;    }

1.2从url获取文件名

public String getFileName(String url) throws IOException {        String filename = "";        boolean isok = false;        // 从UrlConnection中获取文件名称        try {            URL myURL = new URL(url);            URLConnection conn = myURL.openConnection();            if (conn == null) {                return null;            }            Map<String, List<String>> hf = conn.getHeaderFields();            if (hf == null) {                return null;            }            Set<String> key = hf.keySet();            if (key == null) {                return null;            }            for (String skey : key) {                List<String> values = hf.get(skey);                for (String value : values) {                    String result;                    try {                        result = new String(value.getBytes("ISO-8859-1"), "GBK");                        int location = result.indexOf("filename");                        if (location >= 0) {                            result = result.substring(location                                    + "filename".length());                            filename = result                                    .substring(result.indexOf("=") + 1);                            isok = true;                        }                    } catch (UnsupportedEncodingException e) {                        e.printStackTrace();                    }// ISO-8859-1 UTF-8 gb2312                }                if (isok) {                    break;                }            }        } catch (MalformedURLException e) {            e.printStackTrace();        } catch (IOException e) {            e.printStackTrace();        }        return filename;    }

2输出

文件2：ZipController.java
结构：

import com.jfinal.core.Controller;import org.apache.commons.codec.binary.Base64;import javax.servlet.http.HttpServletRequest;import javax.servlet.http.HttpServletResponse;import java.io.*;import java.net.URLEncoder;import org.apache.tools.zip.ZipEntry;import org.apache.tools.zip.ZipOutputStream;public class ZipController extends Controller {    //2.1    public void index() throws IOException {}    //2.2    public void zipAction(String url,InputStream is,ZipOutputStream zos,GetFile gf,byte[] buffer) throws Exception{}    //2.3    public String encodeFileName(HttpServletRequest request, String fileName) throws UnsupportedEncodingException{}}

2.1 index(）–业务处理，压缩，导出。

public void index() throws IOException {        String fileName = "List";        HttpServletResponse response = getResponse();        HttpServletRequest request = getRequest();        response.setHeader("Connection", "close");        response.setHeader("Content-Type", "application/vnd.ms-excel;charset=UTF-8");        String filename = System.currentTimeMillis() + fileName+".zip";        filename = encodeFileName(request, filename);        response.setHeader("Content-Disposition", "attachment;filename=" + filename);        OutputStream out = null;        out = response.getOutputStream();        try {            // create byte buffer            byte[] buffer = new byte[1024];            ZipOutputStream zos = new ZipOutputStream(out);            GetFile gf = new GetFile();            InputStream is= null;            String url1 = "http://xxxxxxxxxxx";            String url2 = "http://xxxxxxxxxxx";            zipAction(url1,is,zos,gf,buffer);            zipAction(url2,is,zos,gf,buffer);            zos.closeEntry();            zos.close();            is.close();        }catch (Exception ioe) {            System.out.println("Error creating zip file" + ioe);        }    }

2.2 zipAction()–处理各种流，压缩具体实现

    public void zipAction(String url,InputStream is,ZipOutputStream zos,GetFile gf,byte[] buffer) throws Exception{        is = gf.getFileInputStream(url);        String fileName1 = gf.getFileName(url);        zos.putNextEntry(new ZipEntry(fileName1));        int length;        while ((length = is.read(buffer)) > 0) {            zos.write(buffer, 0, length);        }    }

2.3 encodeFileName()–文件名处理

    public String encodeFileName(HttpServletRequest request, String fileName) throws UnsupportedEncodingException {        String agent = request.getHeader("USER-AGENT");        if (null != agent && -1 != agent.indexOf("MSIE")) {            return URLEncoder.encode(fileName, "UTF-8");        } else if (null != agent && -1 != agent.indexOf("Mozilla")) {            return "=?UTF-8?B?"+ (new String(Base64.encodeBase64(fileName.getBytes("UTF-8")))) + "?=";        } else {            return fileName;        }    }