java文件操作

2019-11-17 04:07:25

字体：大中小

来源：转载

供稿：网友

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, File access.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
}
}

上一篇：java笔试汇总（2）

下一篇：JAVA面试题(2)