JAVA文件操作大全

1.创建文件夹 File myFolderPath = new File(%%1); try { if (!myFolderPath.exists()) { myFolderPath.mkdir(); } } catch (Exception e) { System.out.println("新建目录操作出错"); e.printStackTrace(); } 2.创建文件 File myFilePath = new File(%%1); try { if (!myFilePath.exists()) { myFilePath.createNewFile(); } FileWriter resultFile = new FileWriter(myFilePath); PrintWriter myFile = new PrintWriter(resultFile); myFile.println(%%2); resultFile.close(); } catch (Exception e) { System.out.println("新建文件操作出错"); e.printStackTrace(); } 3.删除文件 File myDelFile = new File(%%1); try { myDelFile.delete(); } catch (Exception e) { System.out.println("删除文件操作出错"); e.printStackTrace(); } 4.删除文件夹 File delFolderPath = new File(%%1); try { delFolderPath.delete(); //删除空文件夹 } catch (Exception e) { System.out.println("删除文件夹操作出错"); e.printStackTrace(); } 5.删除一个文件下夹所有的文件夹 File delfile=new File(%%1); File[] files=delfile.listFiles(); for(int i=0;i<files.length;i++){ if(files[i].isDirectory()){ files[i].delete(); } } 6.清空文件夹 File delfilefolder=new File(%%1); try { if (!delfilefolder.exists()) { delfilefolder.delete(); } delfilefolder.mkdir(); } catch (Exception e) { System.out.println("清空目录操作出错"); e.printStackTrace(); } 7.读取文件 // 逐行读取数据 FileReader fr = new FileReader(%%1); BufferedReader br = new BufferedReader(fr); String %%2 = br.readLine(); while (%%2 != null) { %%3 %%2 = br.readLine(); } br.close(); fr.close(); 8.写入文件 // 将数据写入文件 FileWriter fw = new FileWriter(%%1); fw.write(%%2); fw.close(); 9.写入随机文件 try { RandomAcessFile logFile=new RandomAcessFile(%%1,"rw"); long lg=logFile.length(); logFile.seek(%%2); logFile.writeByte(%%3); }catch(IOException ioe){ System.out.println("无法写入文件："+ioe.getMessage()); } 10.读取文件属性 // 文件属性的取得 File af = new File(%%1); if (af.exists()) { System.out.println(f.getName() + "的属性如下： 文件长度为：" + f.length()); System.out.println(f.isFile() ? "是文件" : "不是文件"); System.out.println(f.isDirectory() ? "是目录" : "不是目录"); System.out.println(f.canRead() ? "可读取" : "不"); System.out.println(f.canWrite() ? "是隐藏文件" : ""); System.out.println("文件夹的最后修改日期为：" + new Date(f.lastModified())); } else { System.out.println(f.getName() + "的属性如下："); System.out.println(f.isFile() ? "是文件" : "不是文件"); System.out.println(f.isDirectory() ? "是目录" : "不是目录"); System.out.println(f.canRead() ? "可读取" : "不"); System.out.println(f.canWrite() ? "是隐藏文件" : ""); System.out.println("文件的最后修改日期为：" + new Date(f.lastModified())); } if(f.canRead()){ %%2 } if(f.canWrite()){ %%3 } 11.写入属性 File filereadonly=new File(%%1); try { boolean b=filereadonly.setReadOnly(); } catch (Exception e) { System.out.println("拒绝写访问："+e.printStackTrace()); } 12.枚举一个文件夹中的所有文件夹 //import java.io.*; //import java.util.*; ArrayList<String> folderList = new ArrayList<String>(); folderList.add(%%1); for (int j = 0; j < folderList.size(); j++) { File file = new File(folderList.get(j)); File[] files = file.listFiles(); ArrayList<File> fileList = new ArrayList<File>(); for (int i = 0; i < files.length; i++) { if (files[i].isDirectory()) { folderList.add(files[i].getPath()); } else { fileList.add(files[i]); } } for (File f : fileList) { %%2=f.toString(); %%3 } } 13.复制文件夹 //import java.io.*; //import java.util.*; ArrayList<String>folderList=new ArrayList<String>(); folderList.add(%%1); ArrayList<String>folderList2=new ArrayList<String>(); folderList2.add(%%2); for(int j=0;j<folderList.length;j++){ (new File(folderList2[j])).mkdirs(); //如果文件夹不存在 则建立新文件夹 File folders=new File(folderList[j]); String[] file=folders.list(); File temp=null; try { for (int i = 0; i < file.length; i++) { if(folderList[j].endsWith(File.separator)){ temp=new File(folderList[j]+"/"+file[i]); } else{ temp=new File(folderList[j]+"/"+File.separator+file[i]); } FileInputStream input = new FileInputStream(temp); if(temp.isFile()){ FileInputStream input = new FileInputStream(temp); FileOutputStream output = new FileOutputStream(folderList2[j] + "/" + (temp.getName()).toString()); byte[] b = new byte[5120]; int len; while ( (len = input.read(b)) != -1) { output.write(b, 0, len); } output.flush(); output.close(); input.close(); } if(temp.isDirectory()){//如果是子文件夹 folderList.add(folderList[j]+"/"+file[i]); folderList2.add(folderList2[j]+"/"+file[i]); } } } catch (Exception e) { System.out.println("复制整个文件夹内容操作出错"); e.printStackTrace(); } } 14.复制一个文件夹下所有的文件夹到另一个文件夹下 File copyfolders=new File(%%1); File[] copyfoldersList=copyfolders.listFiles(); for(int k=0;k<copyfoldersList.length;k++){ if(copyfoldersList[k].isDirectory()){ ArrayList<String>folderList=new ArrayList<String>(); folderList.add(copyfoldersList[k].getPath()); ArrayList<String>folderList2=new ArrayList<String>(); folderList2.add(%%2+"/"+copyfoldersList[k].getName()); for(int j=0;j<folderList.length;j++){ (new File(folderList2[j])).mkdirs(); //如果文件夹不存在 则建立新文件夹 File folders=new File(folderList[j]); String[] file=folders.list(); File temp=null; try { for (int i = 0; i < file.length; i++) { if(folderList[j].endsWith(File.separator)){ temp=new File(folderList[j]+"/"+file[i]); } else{ temp=new File(folderList[j]+"/"+File.separator+file[i]); } FileInputStream input = new FileInputStream(temp); if(temp.isFile()){ FileInputStream input = new FileInputStream(temp); FileOutputStream output = new FileOutputStream(folderList2[j] + "/" + (temp.getName()).toString()); byte[] b = new byte[5120]; int len; while ( (len = input.read(b)) != -1) { output.write(b, 0, len); } output.flush(); output.close(); input.close(); } if(temp.isDirectory()){//如果是子文件夹 folderList.add(folderList[j]+"/"+file[i]); folderList2.add(folderList2[j]+"/"+file[i]); } } } catch (Exception e) { System.out.println("复制整个文件夹内容操作出错"); e.printStackTrace(); } } } } 15.移动文件夹 ArrayList<String>folderList=new ArrayList<String>(); folderList.add(%%1); ArrayList<String>folderList2=new ArrayList<String>(); folderList2.add(%%2); for(int j=0;j<folderList.length;j++){ (new File(folderList2[j])).mkdirs(); //如果文件夹不存在 则建立新文件夹 File folders=new File(folderList[j]); String[] file=folders.list(); File temp=null; try { for (int i = 0; i < file.length; i++) { if(folderList[j].endsWith(File.separator)){ temp=new File(folderList[j]+"/"+file[i]); } else{ temp=new File(folderList[j]+"/"+File.separator+file[i]); } FileInputStream input = new FileInputStream(temp); if(temp.isFile()){ FileInputStream input = new FileInputStream(temp); FileOutputStream output = new FileOutputStream(folderList2[j] + "/" + (temp.getName()).toString()); byte[] b = new byte[5120]; int len; while ( (len = input.read(b)) != -1) { output.write(b, 0, len); } output.flush(); output.close(); input.close(); } if(temp.isDirectory()){//如果是子文件夹 folderList.add(folderList[j]+"/"+file[i]); folderList2.add(folderList2[j]+"/"+file[i]); } } } catch (Exception e) { System.out.println("复制整个文件夹内容操作出错"); e.printStackTrace(); } } File movefile=new File(%%1); File[] movefiles=movefile.listFiles(); for(int i=0;i<files.length;i++){ if(files[i].isDirectory()){ files[i].delete(); } } movefile.delete(); 16.移动一个文件夹下所有的文件夹到另一个目录下 File movefolders=new File(%%1); File[] movefoldersList=movefolders.listFiles(); for(int k=0;k<movefoldersList.length;k++){ if(movefoldersList[k].isDirectory()){ ArrayList<String>folderList=new ArrayList<String>(); folderList.add(movefoldersList[k].getPath()); ArrayList<String>folderList2=new ArrayList<String>(); folderList2.add(%%2+"/"+movefoldersList[k].getName()); for(int j=0;j<folderList.length;j++){ (new File(folderList2[j])).mkdirs(); //如果文件夹不存在 则建立新文件夹 File folders=new File(folderList[j]); String[] file=folders.list(); File temp=null; try { for (int i = 0; i < file.length; i++) { if(folderList[j].endsWith(File.separator)){ temp=new File(folderList[j]+"/"+file[i]); } else{ temp=new File(folderList[j]+"/"+File.separator+file[i]); } FileInputStream input = new FileInputStream(temp); if(temp.isFile()){ FileInputStream input = new FileInputStream(temp); FileOutputStream output = new FileOutputStream(folderList2[j] + "/" + (temp.getName()).toString()); byte[] b = new byte[5120]; int len; while ( (len = input.read(b)) != -1) { output.write(b, 0, len); } output.flush(); output.close(); input.close(); temp.delete(); } if(temp.isDirectory()){//如果是子文件夹 folderList.add(folderList[j]+"/"+file[i]); folderList2.add(folderList2[j]+"/"+file[i]); } } } catch (Exception e) { System.out.println("复制整个文件夹内容操作出错"); e.printStackTrace(); } } movefoldersList[k].delete(); } } 17.以一个文件夹的框架在另一个目录创建文件夹和空文件 ArrayList<String>folderList=new ArrayList<String>(); folderList.add(%%1); ArrayList<String>folderList2=new ArrayList<String>(); folderList2.add(%%2); for(int j=0;j<folderList.length;j++){ (new File(folderList2[j])).mkdirs(); //如果文件夹不存在 则建立新文件夹 File folders=new File(folderList[j]); String[] file=folders.list(); File temp=null; try { for (int i = 0; i < file.length; i++) { if(folderList[j].endsWith(File.separator)){ temp=new File(folderList[j]+"/"+file[i]); } else{ temp=new File(folderList[j]+"/"+File.separator+file[i]); } FileInputStream input = new FileInputStream(temp); if(temp.isFile()){ if (!temp.exists()) { temp.createNewFile(); } } if(temp.isDirectory()){//如果是子文件夹 folderList.add(folderList[j]+"/"+file[i]); folderList2.add(folderList2[j]+"/"+file[i]); } } } catch (Exception e) { System.out.println("复制整个文件夹内容操作出错"); e.printStackTrace(); } } 18.复制文件 int bytesum = 0; int byteread = 0; File oldfile = new File(%%1); try { if (oldfile.exists()) { //文件存在时 InputStream inStream = new FileInputStream(oldfile); //读入原文件 FileOutputStream fs = new FileOutputStream(new File(%%2,oldfile.getName())); byte[] buffer = new byte[5120]; int length; while ( (byteread = inStream.read(buffer)) != -1) { bytesum += byteread; //字节数 文件大小 System.out.println(bytesum); fs.write(buffer, 0, byteread); } inStream.close(); } } catch (Exception e) { System.out.println("复制单个文件操作出错"); e.printStackTrace(); } 19.复制一个文件夹下所有的文件到另一个目录 File copyfiles=new File(%%1); File[] files=copyfiles.listFiles(); for(int i=0;i<files.length;i++){ if(!files[i].isDirectory()){ int bytesum = 0; int byteread = 0; try { InputStream inStream = new FileInputStream(files[i]); //读入原文件 FileOutputStream fs = new FileOutputStream(new File(%%2,files[i].getName()); byte[] buffer = new byte[5120]; int length; while ( (byteread = inStream.read(buffer)) != -1) { bytesum += byteread; //字节数 文件大小 System.out.println(bytesum); fs.write(buffer, 0, byteread); } inStream.close(); } catch (Exception e) { System.out.println("复制单个文件操作出错"); e.printStackTrace(); } } } 20.提取扩展名 String %%2=(new File(%%1)).getName().split(".")[1]; 21.提取文件名 String %%2=(new File(%%1)).getName().split("//")[1]; 22.提取文件路径 String %%2=(new File(%%1)).getPath(); 23.替换扩展名 File replaceExt=new File(%%1); replaceExt.renameTo(replaceExt.getName().split(".")[0]+"."+%%2); 24.追加路径 %%3=%%2+"/"+%%1 25.移动文件 int bytesum = 0; int byteread = 0; File oldfile = new File(%%1); try { if (oldfile.exists()) { //文件存在时 InputStream inStream = new FileInputStream(oldfile); //读入原文件 FileOutputStream fs = new FileOutputStream(new File(%%2,oldfile.getName())); byte[] buffer = new byte[5120]; int length; while ( (byteread = inStream.read(buffer)) != -1) { bytesum += byteread; //字节数 文件大小 //System.out.println(bytesum); fs.write(buffer, 0, byteread); } inStream.close(); oldfile.delete(); } } catch (Exception e) { System.out.println("复制单个文件操作出错"); e.printStackTrace(); } 26.移动一个文件夹下所有文件到另一个目录 File movefile=new File(%%1); File[] movefiles=movefile.listFiles(); for(int i=0;i<movefiles.length;i++){ if(movefiles[i].isFile()){ int bytesum = 0; int byteread = 0; File oldfile = new File(movefiles[i]); try { if (oldfile.exists()) { //文件存在时 InputStream inStream = new FileInputStream(oldfile); //读入原文件 FileOutputStream fs = new FileOutputStream(new File(%%2,oldfile.getName())); byte[] buffer = new byte[5120]; int length; while ( (byteread = inStream.read(buffer)) != -1) { bytesum += byteread; //字节数 文件大小 //System.out.println(bytesum); fs.write(buffer, 0, byteread); } inStream.close(); oldfile.delete(); } } catch (Exception e) { System.out.println("复制单个文件操作出错"); e.printStackTrace(); } } } 27.指定目录下搜索文件 private void doSearch(String filter, String path) { File file = new File(path); if(file.exists()) { if(file.isDirectory()) { File[] fileArray = file.listFiles(); for(File f:fileArray) { if(f.isDirectory()) { doSearch(filter,f.getPath()); } else { if(f.getName().indexOf(filter) >= 0) { countFiles++; result.append(f.getPath() + "/r/n"); } } statusShow1.setText(f.getPath()); } statusShow2.setText("The numbers of files had been found:" + countFiles); } else { System.out.println("Couldn't open the path!"); } } else { System.out.println("The path had been apointed was not Exist!"); } } 28.打开对话框 JFileChooser Jfc = new JFileChooser(); //建立选择档案对话方块盒 Jfc %%1 = Jfc.getSelectedFile(); 29.文件分割 //import java.io.* try { File f=new File(%%1); FileInputStream fileInputStream = new FileInputStream(f); byte[] buffer = new byte[fileInputStream.available()]; FileInputStream.read(buffer); fileInputStream.close(); String strFileName = f.getName(); FileOutputStream fileOutputStream = new FileOutputStream(new File(%%2+"//"+ strFileName + "1")); fileOutputStream.write(buffer,0,buffer.length/2); fileOutputStream.close(); fileOutputStream = new FileOutputStream(new File(%%2+"//"+ strFileName + "2")); fileOutputStream.write(buffer, buffer.length/2, buffer.length-buffer.length/2); fileOutputStream.close(); } catch (ArrayIndexOutOfBoundsException e) { System.out.print("using FileStreamDemo src des"); e.printStackTrace(); } catch(IOException e){ e.printStackTrace(); } 30.文件合并 //import java.io.* String strFileName = %%1.substring(%%1.LastIndexOf("//") + 1); try { FileInputStream fileInputStream1 = new FileInputStream(new File(%%2 + strFileName + "1")); FileInputStream fileInputStream2 = new FileInputStream(new File(%%2 + strFileName + "2")); byte[] buffer = new byte[fileInputStream1.available()+fileInputStream2.available()]; FileInputStream.read(buffer, 0, fileInputStream1.available()); FileInputStream2.read(buffer, fileInputStream1.available(), fileInputStream2.available()); fileInputStream.close(); fileInputStream2.close(); FileOutputStream fileOutputStream = new FileOutputStream(new File(%%2+"//"+ strFileName)); fileOutputStream.write(buffer,0,buffer.length); fileOutputStream.close(); catch(IOException e){ e.printStackTrace(); } 31.文件简单加密 //读文件 FileStream fsr = new FileStream(%%1, FileMode.Open, FileAccess.Read); byte[] btArr = new byte[fsr.Length]; fsr.Read(btArr, 0, btArr.Length); fsr.Close(); for (int i = 0; i < btArr.Length; i++) //加密 { int ibt = btArr[i]; ibt += 100; ibt %= 256; btArr[i] = Convert.ToByte(ibt); } //写文件 string strFileName = Path.GetExtension(%%1); FileStream fsw = new FileStream(%%2+"/" + "enc_" + strFileName, FileMode.Create, FileAccess.Write); fsw.Write(btArr, 0, btArr.Length); fsw.Close(); 32.文件简单解密 FileStream fsr = new FileStream(%%1, FileMode.Open, FileAccess.Read); byte[] btArr = new byte[fsr.Length]; fsr.Read(btArr, 0, btArr.Length); fsr.Close(); for (int i = 0; i < btArr.Length; i++)　//解密 { int ibt = btArr[i]; ibt -= 100; ibt += 256; ibt %= 256; btArr[i] = Convert.ToByte(ibt); } //写文件 string strFileName = Path.GetExtension(%%1); FileStream fsw = new FileStream(%%2 +"/" + strFileName, FileMode.Create, FileAccess.Write); fsw.Write(btArr, 0, btArr.Length); fsw.Close(); 33.文件简单解密 //import java.io.* try { File f=new File(%%1); String strFileName = f.getName(); FileInputStream fileInputStream = new FileInputStream(%%2+"//enc_"+strFilename); byte[] buffer = new byte[fileInputStream.available()]; FileInputStream.read(buffer); fileInputStream.close(); for(int i=0;i<buffer.length;i++) { int ibt=buffer[i]; ibt-=100; ibt+=256; ibt%=256; buffer[i]=(byte)ibt; } FileOutputStream fileOutputStream = new FileOutputStream(f); fileOutputStream.write(buffer,0,buffer.length); fileOutputStream.close(); } catch(ArrayIndexOutOfBoundException e){ e.printStackTrace(); } catch(IOException e){ e.printStackTrace(); } 34.读取ini文件属性 //import java.io.* //import java.util.*; //import java.util.regex.*; //private HashMap configMap=null; private Map configMap=null; if(configMap==null) { String strLine=null; String currentNode=null; String previousNode=null; Vector vec=new Vector(); int row=0; FileReader fileReader = new FileReader(%%1); BufferedReader bufferedReader=new BufferedReader(fileReader); try { while((strLine=bufferedReader.readLine())!=null) { String oneLine=strLine.trim(); if(oneLine.length()>=1) { Pattern p=Pattern.compile("//[//s*.*//s*//]"); int nodelen=oneLine.split("[;]").length; String[] strArray1=new String[4]; if(nodelen==1) { oneLine=oneLine.split("[;]")[0].trim(); } else if(nodelen==2) { strArray1[3]=oneLine.split("[;]")[1].trim(); oneLine=oneLine.split("[;]")[0].trim(); } Matcher m=p.matche(oneLine); if(m.matches()) { strArray1[0]="@Node"; strArray1[1]=oneLine; strArray1[2]=""; } else { int keylen=oneLine.split("=").length; if(keylen==1) { strArray1[0]="@Key"; strArray1[1]=oneLine.split("=")[0]; strArray1[2]=""; } else if(kenlen==2) { strArray1[0]="@Key"; strArray1[1]=oneLine.split("=")[0]; strArray1[2]=oneLine.split("=")[1]; } else { strArray1[0]="@ElementError"; strArray1[1]=""; strArray1[2]=""; strArray1[3]=""; } } if(strArray1[0].equals("@Node")) { previousNode=currentNode; currentNode=strArray1[1]; if(row>0) { configMap.put(previousNode,vec.elementAt(0)); //"size:"+configMap.size() vec.clear(); row=0; } } else if(strArray1[0].equals("@Key") && row==0) { Properties ht=new Properties(); ht.setProperty(strArray1[1],strArray1[2]); vec.add(0,ht); row++; } } else if(strArray1[0].equals("@Key") && row>0) { Properties ht2=new Properties(); ht2.put(strArray1[1],strArray1[2]); vec.clear(); vec.add(0,ht2); row++; } } } configMap.put(currentNode,vec.elementAt(0)); } catch (FileNotFoundException e) { configMap=null; e.printStackTrace(); } catch (IOException e) { configMap=null; e.printStackTrace(); } finally { vec.clear(); bufferedReader.close(); fileReader.close(); } } String nodeKey="["+%%2+"]"; Properties ht=(Properties)configMap.get(nodeKey); //"ht:"+ht.toString() //"key:"+%%3 CString %%4=null; if(ht.containsKey(%%3)) { try { %%4=ht.getProperty(%%3); } catch (NullPointException e) { e.printStackTrace(); } } 35.合并一个文件下所有的文件 File combinefiles=new File(%%1); File[] files=combinefiles.listFiles(); FileOutputStream fs; try { fs=new FileOutputStream(new File(%%2)); } catch(IOException e){ e.printStackTrace(); } for(int i=0;i<files.length;i++){ if(files[i].isFile()){ int bytesum=0; int byteread=0; try { FileInputStream inStream=new FileInputStream(files[i]); byte[] buffer = new byte[5120]; int length; while((byteread=inStream.read(buffer))!=-1){ bytesum+=byteread; fs.write(buffer,0,byteread); } inStream.close(); } catch(Exception e){ //复制文件出错 e.printStackTrace(); } } } try { fs.close(); } catch(IOException e){ { e.printStackTrace(); } 36.写入ini文件属性 //import java.io.* //import java.util.*; //import java.util.regex.*; //private HashMap configMap=null; private Map configMap=null; if(configMap==null) { String strLine=null; String currentNode=null; String previousNode=null; Vector vec=new Vector(); int row=0; FileReader fileReader = new FileReader(%%1); BufferedReader bufferedReader=new BufferedReader(fileReader); try { while((strLine=bufferedReader.readLine())!=null) { String oneLine=strLine.trim(); if(oneLine.length()>=1) { Pattern p=Pattern.compile("//[//s*.*//s*//]"); int nodelen=oneLine.split("[;]").length; String[] strArray1=new String[4]; if(nodelen==1) { oneLine=oneLine.split("[;]")[0].trim(); } else if(nodelen==2) { strArray1[3]=oneLine.split("[;]")[1].trim(); oneLine=oneLine.split("[;]")[0].trim(); } Matcher m=p.matche(oneLine); if(m.matches()) { strArray1[0]="@Node"; strArray1[1]=oneLine; strArray1[2]=""; } else { int keylen=oneLine.split("=").length; if(keylen==1) { strArray1[0]="@Key"; strArray1[1]=oneLine.split("=")[0]; strArray1[2]=""; } else if(kenlen==2) { strArray1[0]="@Key"; strArray1[1]=oneLine.split("=")[0]; strArray1[2]=oneLine.split("=")[1]; } else { strArray1[0]="@ElementError"; strArray1[1]=""; strArray1[2]=""; strArray1[3]=""; } } if(strArray1[0].equals("@Node")) { previousNode=currentNode; currentNode=strArray1[1]; if(row>0) { configMap.put(previousNode,vec.elementAt(0)); //"size:"+configMap.size() vec.clear(); row=0; } } else if(strArray1[0].equals("@Key") && row==0) { Properties ht=new Properties(); ht.setProperty(strArray1[1],strArray1[2]); vec.add(0,ht); row++; } } else if(strArray1[0].equals("@Key") && row>0) { Properties ht2=new Properties(); ht2.put(strArray1[1],strArray1[2]); vec.clear(); vec.add(0,ht2); row++; } } } configMap.put(currentNode,vec.elementAt(0)); } catch (FileNotFoundException e) { configMap=null; e.printStackTrace(); } catch (IOException e) { configMap=null; e.printStackTrace(); } finally { vec.clear(); bufferedReader.close(); fileReader.close(); } } String nodeKey="["+%%2+"]"; Properties ht=null; if(configMap.containsKey(nodeKey)) { ht=(Properties)configMap.get(nodeKey); } else { ht=(Properties)configMap.get(nodeKey,%%3); } try { ht.setProperty(%%3,%%4); } catch (NullPointException e) { e.printStackTrace(); } FileWriter fw = new FileWriter(%%1); BufferedWriter bw=new BufferedWriter(fw); Set keys=configMap.keySet(); Iterator ite=keys.iterator(); while(ite.hasNext()) { String oneKey=(String)ite.next(); bw.WriteLine(oneKey); ht=(Properties)configMap.get(oneKey); ht.list(new PrintWriter(bw,true)); } 37.获得当前路径 this.getClass().getResource("/").getPath() 38.读取XML数据库 //import java.io.*; //import javax.xml.parsers.*; //import org.xml.sax.*; //import org.w3c.dom.*; private Document document; File xml_file=new File(%%1); DocumentBuilderFactory factory=DocumentBuilderFactory.newInstance(); try { DocumentBuilder builder=factory.newDocumentBuilder(); document=builder.parse(xml_file); } catch(Exception e) { e.printStackTrace(); } String subNodeTag=%%2; Element rootNode=document.getDocumentElement(); //%%2="serverList" //%%4="id" //%%6="port" //%%3="server" //%%5="ipaddr" NodeList nlist=rootNode.getElementsByTagName(subNodeTag); int len=nlist.getLength(); Node x=null; for(int i=0;i<len;i++) { x=nlist.item(i); String getNodeAttrValue=null; NamedNodeMap attrList=node.getAttributes(); for(int j=0;j<attrList.getLength();j++) { if(attrList.item(j).getNodeName().compareTo(%%7)==0) { getNodeAttrValue=attrList.item(j).getNodeValue(); break; } } if(getNodeAttrValue.compareTo(%%8)==0) break; } String %%9=null; if(x!=null) { NodeList nlist=node.getChildNodes(); int len=nlist.getLength(); Node currentNode; String nodeName; for(int i=0;i<len;i++) { currentNode=nlist.item(i); nodeName=currentNode.getNodeName(); if(nodeName.equals(%%5)==0) { %%9=document.getElementValue(currentNode); break; } } } 39.写入XML数据库 //import java.io.*; //import javax.xml.parsers.*; //import org.xml.sax.*; //import org.w3c.dom.*; //import javax.xml.transform.*; //import javax.xml.transform.dom.*; //import javax.xml.transform.stream.*; private Document document; private Element node; File xml_file=new File(%%1); DocumentBuilderFactory factory=DocumentBuilderFactory.newInstance(); try { DocumentBuilder builder=factory.newDocumentBuilder(); document=builder.parse(xml_file); } catch(Exception e) { e.printStackTrace(); } String subNodeTag=%%2; Element rootNode=document.getDocumentElement(); //%%2="serverList" //%%4="id" //%%6="port" //%%3="server" //%%5="ipaddr" NodeList nlist=rootNode.getElementByTagName(subNodeTag); node=document.createElement(%%3); node.setAttribute(%%4,nlist.getLength()+1).toString()); node.appendChild(document.createTextNode("/n"); Element ipNode=document.createElement(%%5); ipNode.appendChild(document.createTextNode(%%8)); node.appendChild(ipNode); node.appendChild(document,createTextNode("/n"); Element port=document.createElement(%%6); port.appendChild(document.createTextNode(%%9)); node.appendChild(port); node.appendChild(document,createTextNode("/n"); nlist.appendChild(node); TransformerFactory tFactory=TransformerFactory.newInstance(); Transformer transformer=null; try { transformer=tFactory.newTransformer(); DOMSource source=new DOMSource(document); StreamResult result=new StreamResult(xml_file); transformer.transform(source,result); } catch(Exception e) { e.printStackTrace(); } 40.ZIP压缩文件 //import java.io.*; //import java.util.zip.*; //创建文件输入流对象 FileInputStream fis=new FileInputStream(%%1); //创建文件输出流对象 FileOutputStream fos=new FileOutputStream(%%2); //创建ZIP数据输出流对象 ZipOutputStream zipOut=new ZipOutputStream(fos); //创建指向压缩原始文件的入口 ZipEntry entry=new ZipEntry(args[0]); zipOut.putNextEntry(entry); //向压缩文件中输出数据 int nNumber; byte[] buffer=new byte[1024]; while((nNumber=fis.read(buffer))!=-1) zipOut.write(buffer,0,nNumber); //关闭创建的流对象 zipOut.close(); fos.close(); fis.close(); } catch(IOException e) { System.out.println(e); } 41.ZIP解压缩 //import java.io.*; //import java.util.zip.*; try{ //创建文件输入流对象实例 FileInputStream fis=new FileInputStream(%%1); //创建ZIP压缩格式输入流对象实例 ZipInputStream zipin=new ZipInputStream(fis); //创建文件输出流对象实例 FileOutputStream fos=new FileOutputStream(%%2); //获取Entry对象实例 ZipEntry entry=zipin.getNextEntry(); byte[] buffer=new byte[1024]; int nNumber; while((nNumber=zipin.read(buffer,0,buffer.length))!=-1) fos.write(buffer,0,nNumber); //关闭文件流对象 zipin.close(); fos.close(); fis.close(); } catch(IOException e) { System.out.println(e); } 42.递归删除目录中的文件 //import java.io.*; //import java.util.*; ArrayList<String> folderList = new ArrayList<String>(); folderList.add(%%1); for (int j = 0; j < folderList.size(); j++) { File file = new File(folderList.get(j)); File[] files = file.listFiles(); ArrayList<File> fileList = new ArrayList<File>(); for (int i = 0; i < files.length; i++) { if (files[i].isDirectory()) { folderList.add(files[i].getPath()); } else { fileList.add(files[i]); } } for (File f : fileList) { f.delete(); } } 43.ZIP压缩文件夹 //import java.io.*; //import org.apache.tools.zip.ZipOutputStream; //这个包在ant.jar里，要到官方网下载 //import java.util.zip.*; try { String zipFileName = %%2; //打包后文件名字 File f=new File(%%1); ZipOutputStream out = new ZipOutputStream(new FileOutputStream(zipFileName)); String base= ""; if (f.isDirectory()) { File[] fl = f.listFiles(); out.putNextEntry(new org.apache.tools.zip.ZipEntry(base + "/")); base = base.length() == 0 ? "" : base + "/"; for (int i = 0; i < fl.length; i++) { zip(out, fl[i], base + fl[i].getName()); } }else { out.putNextEntry(new org.apache.tools.zip.ZipEntry(base)); FileInputStream in = new FileInputStream(f); int b; while ( (b = in.read()) != -1) { out.write(b); } in.close(); } out.close(); }catch (Exception ex) { ex.printStackTrace(); } 44.Java验证DTD try { InputStream in=new FileInputStream(filePath); SAXReader saxReader = new SAXReader(); this.document = saxReader.read(in); DocumentBuilderFactory factory = null; factory = DocumentBuilderFactory.newInstance(); //进行dtd检查 factory.setValidating(true); } catch (Exception e) { } 45.验证Schema String xsdFileName = /"Q:////_dev_stu////xsdtest////src////note.xsd/"; try { //创建默认的XML错误处理器 XMLErrorHandler errorHandler = new XMLErrorHandler(); //获取基于 SAX 的解析器的实例 SAXParserFactory factory = SAXParserFactory.newInstance(); //解析器在解析时验证 XML 内容。 factory.setValidating(true); //指定由此代码生成的解析器将提供对 XML 名称空间的支持。 factory.setNamespaceAware(true); //使用当前配置的工厂参数创建 SAXParser 的一个新实例。 SAXParser parser = factory.newSAXParser(); //创建一个读取工具 SAXReader xmlReader = new SAXReader(); //获取要校验xml文档实例 Document xmlDocument = (Document) xmlReader.read(new File(xmlFileName)); //设置 XMLReader 的基础实现中的特定属性。核心功能和属性列表可以在 [url]http://sax.sourceforge.net/?selected=get-set[/url] 中 找到。 parser.setProperty( /"http://java.sun.com/xml/jaxp/properties/schemaLanguage", /"http://www.w3.org/2001/XMLSchema"); parser.setProperty( /"http://java.sun.com/xml/jaxp/properties/schemaSource", /"file:/" + xsdFileName); //创建一个SAXValidator校验工具，并设置校验工具的属性 SAXValidator validator = new SAXValidator(parser.getXMLReader()); //设置校验工具的错误处理器，当发生错误时，可以从处理器对象中得到错误信息。 validator.setErrorHandler(errorHandler); //校验 validator.validate(xmlDocument); XMLWriter writer = new XMLWriter(OutputFormat.createPrettyPrint()); //如果错误信息不为空，说明校验失败，打印错误信息 if (errorHandler.getErrors().hasContent()) { System.out.println(/"XML文件通过XSD文件校验失败！/"); writer.write(errorHandler.getErrors()); } else { System.out.println(/"Good! XML文件通过XSD文件校验成功！/"); } } catch (Exception ex) { System.out.println(/"XML文件: /" + xmlFileName + /" 通过XSD文件:/" + xsdFileName + /"检验失败。/n原因： /" + ex.getMessage ()); ex.printStackTrace(); } } 46.Grep //import java.util.regex.Pattern; //import java.util.regex.Matcher; //import java.io.FileReader; //import java.io.BufferedReader; //import java.io.IOException; /** * Simple implementation of the ubiquitous grep command. * First argument is the regular expression to search for (remember to * quote and/or escape as appropriate). All following arguments are * filenames to read and search for the regular expression. * * Created: April, 2002 * @author Ron Hitchens (ron@ronsoft.com) * @version $Id: SimpleGrep.java,v 1.1 2002/05/07 02:21:08 ron Exp $ */ public static void main (String [] argv) throws Exception { if (argv.length < 2) { // 如果参数行没有输入参数，结束程序 System.out.println ("Usage: regex file [ ... ]"); return; } Pattern pattern = Pattern.compile (argv [0]); // 第一个参数为需要匹配的字符串 Matcher matcher = pattern.matcher (""); // 一次读取各个文件 for (int i = 1; i < argv.length; i++) { String file = argv [i]; // 第2个参数开始，均为文件名。 BufferedReader br = null; String line; try { br = new BufferedReader (new FileReader (file)); // 打开文件 } catch (IOException e) { // 没有打开文件，则产生异常 System.err.println ("Cannot read '" + file + "': " + e.getMessage()); continue; } while ((line = br.readLine()) != null) { // 读入一行，直到文件结束 matcher.reset (line); // 匹配字符串 if (matcher.find()) { // 如果有匹配的字符串，则输出 System.out.println (file + ": " + line); } } br.close(); // 关闭文件 } } 本文来自CSDN博客，转载请标明出处：http://blog.csdn.net/chinayaosir/archive/2009/08/28/4492671.aspx