Java对各种文件的操作详解

i tream.close(); %>

整个文件夹拷贝

<%@ age contentType=\"text/html;charset=gb2312\"%> <%@ age import=\"java.io.*\" %> <%String url1=\"C:/aaa\"; tring url2=\"d:/java/\"; (new File(url2)).mkdirs();

File[] file=(new File(url1)).listFiles(); for(int i=0;iFileI utStream i ut=new FileI utStream(file[i]);

FileOutputStream output=new FileOutputStream(url2+\"/\"+(file[i].getName()).toString()); yte[] =new yte[1024*5]; int le

while((len=i ut.read(b))!=-1){ output.write(b,0,len); }

output.flush(); output.close(); i ut.close(); } } %>

JAVA天堂

文件下载

<%@ age contentType=\"text/html charset=gb2312\"%> <%@ age import=\"java.io.*\" %> <%

tring fileName = \"newFile.txt\".toString(); //读到流中

I utStream i tream=new FileI utStream(\"c://测试//newFile.txt\"); //设置输出的格式 re o e.reset();

re o e.setContentType(\"text/plain\");

re o e.addHeader(\"Content-Di osition\ //循环取出流中的数据 yte[] = ew yte[100]; int le

ervletOutputStream outStream = re o e.getOutputStream();

while((len=i tream.read(b)) gt;0) outStream.write(b,0,len); outStream.flush(); outStream.close(); i tream.close(); %>

数据库字段中的文件下载

<%@ age contentType=\"text/html;charset=gb2312\"%> <%@ age import=\"java.util.*,java.sql.*,java.io.*\"%> <%

tring id = request.getParameter(\"id\"); if(id==null)

{ throw ew Exceptio (\"没有找到图片\"); } else { try {

com.gzrealmap.lib.jdbc.JDBCUtil qlBean= com.gzrealmap.lib.jdbc.JDBCUtil.getI tance(); qlBean.co ect();

tring ql = \"select * from i ernew where id = \"\"+79+\"\"\";

ResultSet r = qlBean.queryforUpdate(sql); rs.next();

//String fileNamed = rs.getString(\"imageName\"); tring file= rs.getString(\"acc\");

//String fileName = ew tring(fileNamedb.getBytes(),\"iso-8859-1\"); tring fileName = \"a.jpg\";

re o e.setHeader(\"Content-Di osition\ JAVA天堂

tring filter = fileName.su tring(fileName.lastIndexOf(\".\"));

if(filter.equals(\".txt\")) {

re o e.setContentType(\"text/plain\"); }

else if(filter.equals(\".doc\")||filter.equals(\".dot\")) {

re o e.setContentType(\"a lication/msword\"); JAVA天堂 } else {

re o e.setContentType(\"image/jpeg;charset=GB2312\"); }

ervletOutputStream o = re o e.getOutputStream(); //o.write(file); out.println(file); //o.flush();

//o.close(); qlBean.disco ect(); }

catch(Exceptio ex) {

out.println(ex.getMe age()); }

} %>

把网页保存成文件

<%@ age contentType=\"text/html;charset=gb2312\"%> <%@ age import=\"java.text.*,java.util.*,java.net.*,java.io.*\"%> <%

URL tdURL = ull; ufferedReader tdI = ull; rintWriter tdOut = ull; try {

tdURL = ew URL(\"http://www.163.com\"); }

catch (MalformedURLExceptio e) { throw e; } try {

//将字节流转变成为字符流

tdI = ew ufferedReader(new I utStreamReader(stdURL.ope tream())); tring theFileName = \"c://测试//163.html\";

tdOut = ew rintWriter(new ufferedWriter(new FileWriter(theFileName.toString()))); }

catch (IOExceptio e) { }

/***把URL指定的页面以流的形式读出，写成指定的文件***/ try {

tring trHtml = \"\";

while((strHtml = tdIn.readLine())!=null) { tdOut.println(strHtml); } }

catch (IOExceptio e) { throw e;

} finally { try { if(stdI != ull) tdIn.close(); if(stdOut != ull) tdOut.close(); }

catch (Exceptio e) { ystem.out.println(e); } } %>

直接下载网上的文件

<%@ age contentType=\"text/html;charset=gb2312\"%> <%@ age import=\"java.io.*\"%> <%@ age import=\"java.net.*\"%> <%

int ytesum=0; int yteread=0;

URL url = ew URL(\"http://java.chinaitlab.com/UploadFiles_8734/200611/20061116101405957.gif\");

yte[] uffer =new yte[1444];

while ((byteread=i tream.read(buffer))!=-1) {

out.println(\"

//System.out.println(bytesum); fs.write(buffer,0,byteread); }

%>

按行读文件

<%@ age contentType=\"text/html charset=gb2312\" %> <%@ age import=\"java.io.*\" %> <%

FileReader myFileReader=new FileReader(\"c:/哈哈.txt\");

BufferedReader myBufferedReader=new ufferedReader(myFileReader); String myString=null;

String resultString=new tring();

while((myString=myBufferedReader.readLine())!=null) { resultString=resultString+myString+\"< r>\"; }

out.println(resultString); myFileReader.close(); %>

对word文档的处理（上传与下载）

<%@ age contentType=\"a lication/msword\" %> <%

re o e.setHeader(\"Content-di osition\线上浏览方式 // re o e.setHeader(\"Content-di osition\下载方式 //以上这行设定传送到前端浏览器时的档名为test1.doc //就是靠这一行，让前端浏览器以为接收到一个word档 %>

//然后输出动态内容就可以得到一个word文档了 1,打开：

1）文件头上加：<%@ age contentType=\"a lication/msword\"%> xml文件里：

lt;exte io gt;doclt;mime-type>a lication/msword

2）可以用js,以下代码来自引用：

<%@ age contentType=\"text/html;charset=gb2312\" import= \"java.io.*\"%> < cript>

var wrd=new ActiveXObject(\"Word.A lication\") wrd.visible=true

alert (\"您的\"+wrd.A lication.Caption+\"安装路径为： \"+wrd.A lication.Path+\" 版本号是：\"+ wrd.A lication.version+\" 注册使用者是：\"+wrd.A lication.UserName) wrd.Documents.Add()

//wrd.Documents.Open(\"c:\\exam.doc\") wrd.Selection.TypeText(\"Thi i ome text.\") wrd.A lication.Activate()

wrd.ActiveDocument.SaveAs(\"c:\\exam111.doc\") wrd=null

2，下载：

<%@ age contentType=\"text/html;charset=gb2312\" import= \"java.io.*\"%> <%// 得到文件名字和路径 tring filename = \"j .doc\"; tring filepath = \"C:\\\";

// 设置响应头和下载保存的文件名

re o e.setContentType(\"A LICATION/OCTET-STREAM\");

re o e.setHeader(\"Content-Di osition\

// 打开指定文件的流信息

java.io.FileI utStream fileI utStream = ew java.io.FileI utStream(filepath + filename); //FileOutputStream out = ew FileOutputStream(filepath+\"测试\\\" + filename); // 写出流信息 int i;

while ((i=fileI utStream.read()) != -1) { JAVA天堂 out.write(i); }

fileI utStream.close();

out.close(); %>