I'm trying to use Fork/Join Mechanism ( List>> forks ) mechanism for searching all file on disk 'D:/'.
Here is the code. I got realisation of this mechanism from JLS.
public class FileFound_02 {
public static void main(String[] args) {
String searchword = null;
System.out.println("Andrey3k");
// Get Search word from arguments
if( args.length > 0 ) {
searchword = args[0];
System.out.println("____ args.length " + searchword);
}
// Get Disk Drives
File[] rootDrive = File.listRoots();
for(File sysDrive : rootDrive){
System.out.println("Drive : " + sysDrive);
System.out.println("Drive getAbsolutePath: " + sysDrive.getAbsolutePath());
// Scanning D Disk
if( sysDrive.getAbsolutePath().startsWith("D:") ) {
System.out.println("sysDrive.getAbsolutePath(): " + sysDrive.getAbsolutePath());
if( searchword != null ) {
ForkJoinPool forkJoinPool = new ForkJoinPool() ;
List<File> directories = forkJoinPool.invoke(new ScanningDirectory( new File( sysDrive.getAbsolutePath() ), searchword) );
for (int i = 0; i < directories.size(); i++) {
File file = (File) directories.get(i);
System.out.println(file.getAbsolutePath());
}
}
}
}
}
}
public class ScanningDirectory extends RecursiveTask<List<File>> {
File file;
String searchword = "";
public ScanningDirectory(File file, String searchword) {
this.file = file;
this.searchword = searchword;
}
#Override
protected List<File> compute() {
//
List<RecursiveTask<List<File>>> forks = new LinkedList<>();
List files = new ArrayList();
if (file.isDirectory()) {
for (File childFile : file.listFiles()) {
ScanningDirectory task = new ScanningDirectory(childFile, searchword);
forks.add(task);
task.fork();// запусткаем
}
for (RecursiveTask<List<File>> task : forks) {
files.addAll(task.join()); // ждем выполнения задач и результат
}
}
return files ;
}
}
Console says:
*Exception in thread "main" java.lang.NullPointerException
at andrey3k.FileFound_02.main(FileFound_02.java:40)
Caused by: java.lang.NullPointerException
at andrey3k.ScanningDirectory.compute(ScanningDirectory.java:34)
at andrey3k.ScanningDirectory.compute(ScanningDirectory.java:1)
... 7 more**
What's the problem ??? How can I fix it ???
Related
I am trying to read package and class name from file. In the below code fileEntry.getName() is giving me output C:User\mywork\Myproject\target\generated-source\java\demo\Project.java. I want to get only demo.Project as an output. Appreciate suggestion thank you
public void listFilesForFolder(final File folder) {
for (final File fileEntry : folder.listFiles()) {
if (fileEntry.isDirectory()) {
listFilesForFolder(fileEntry);
} else {
System.out.println(fileEntry.getName());
//C:User\mywork\Myproject\target\generated-source\java\demo\Project.java
}
}
}
I suppose you only need to find java class files and you want inner packages declared as package1.package2.demo.Project. You can do some String manipulation to get that output.
public static String FILE_SEPARATOR = System.getProperty("file.separator");
public static void listFilesForFolder(final File folder) {
for (final File fileEntry : folder.listFiles()) {
if (fileEntry.isDirectory()) {
listFilesForFolder(fileEntry);
} else {
if (!fileEntry.getName().endsWith(".java")) {
continue;
}
String absolutePath = fileEntry.getAbsolutePath();
String javaPackageSeparator = FILE_SEPARATOR + "java" + FILE_SEPARATOR;
int indexOf = absolutePath.indexOf(javaPackageSeparator);
if (indexOf > -1) {
String javaFilePath = absolutePath.substring(indexOf, absolutePath.length());
String strippedJavaSeparator = javaFilePath.replace(javaPackageSeparator, "");
String[] constructProperPackageName = strippedJavaSeparator.split(Pattern.quote(FILE_SEPARATOR));
String packageName = "";
String className = "";
for (int i = 0; i < constructProperPackageName.length; i++) {
if (i == constructProperPackageName.length - 1) {
className = constructProperPackageName[i].replace(".java", "");
continue;
}
packageName += constructProperPackageName[i] + ".";
}
System.out.println(packageName + className);
}
}
}
}
Produces output as following:
com.company.exception.handler.AbstractExceptionHandler
com.company.exception.handler.IExceptionHandler
com.company.exception.handler.APIRequestExceptionHandler
...
A simple scan across the root / source directory using Files.find will return all java files, and then you can adjust the path to generate package name.
Path srcDir = Path.of("src");
BiPredicate<Path, BasicFileAttributes> dotjava = (p,a) -> a.isRegularFile() && p.getFileName().toString().endsWith(".java");
try(var java = Files.find(srcDir, Integer.MAX_VALUE, dotjava)) {
java.map(p -> srcDir.relativize(p).toString().replaceAll("\\.java$", "").replace(File.separator, "."))
.forEach(System.out::println);
}
here is a java program that allows to display the files of each directory
the problem how to display the result in a textarea
private static void
findFilesRecursively(File file, Collection<File> all, final String extension) {
final File[] children = file.listFiles(new FileFilter() {
public boolean accept(File f) {
return f.getName().endsWith(extension) ;
}}
);
if (children != null) {
//Pour chaque fichier recupere, on appelle a nouveau la methode
for (File child : children) {
all.add(child);
findFilesRecursively(child, all, extension);
}
}
}
public static void main(String[] args)
{
//try {
final Collection<File> all = new ArrayList<File>();
// JFileChooser fc = new JFileChooser(".");
// int returnVal = fc.showOpenDialog(null);
findFilesRecursively(new File("c:\\repertoire"), all,"");
//File outputFile = new File("C:\\Users\\21365\\Desktop\\tt.txt");
//FileOutputStream fos = new FileOutputStream(outputFile);
for (int i = 0; i < all.size(); i++) {
for (File file : all) {
if(file.isDirectory()==true){
System.out.println("le repertoire \t"+file.getName()+"\t contien");
}else{
You should not iterate through your list twice - get rid of one of these 2 for loops :
for (int i = 0; i < all.size(); i++) {
for (File file : all) {
Also instead of using System.out.println(…) to print to console, just create a JFrame / JTextArea and use its append(String text) method, eg :
if (file.isDirectory() == true) {
yourTextArea.append("le repertoire \t" + file.getName() + "\t contien");
} else {
yourTextArea.append(file.getName());
}
Given the below FileRepository class, how can I optimise the file search as I am dealing with 500 or more client directories. Perhaps I can re-write the below using Streams?
I need to look at all customer directories at first level, and then foreach customer directories look a level below and only take into consideration yesterday's folder which is something like COB02Oct2010. I have written a DateHelper to return me this this previous working day date to then only consider the sub-directories that is relevant...then I look at the matching file pattern that resides in that directory to get the file to send.
Can I simply this using Paths and DirectoryStream?
public class FileRepository {
public List<File> getFilesToSend(String sourcePath, String pattern, String format) {
List<File> files = new ArrayList<>();
File[] customerDir = getCustomerDirs(sourcePath);
for (int i = 0; i < clientDirs.length; i++) {
files.addAll(processClientDirectory(clientDirs[i], pattern, format));
}
return files;
}
private List<File> processClientDirectory(File clientDir, String pattern, String format) {
List<File> result = new ArrayList<>();
pattern = pattern.toLowerCase(Locale.ENGLISH);
format = Constants.EXTENSION_SEPARATOR + format.toLowerCase(Locale.ENGLISH); //add a "."
File cobDir = new File(clientDir, "COB" + DateHelper.getPreviousWorkingDay());
getFilesToProcess(result, cobDir, pattern, format);
return result;
}
private void getFilesToProcess(List<File> result, File cobDir, String pattern, String format) {
if (!cobDir.exists()) {
return;
}
File[] files = cobDir.listFiles(pathName -> {
if (pathName.isDirectory()) {
return true;
}
if (!pathName.isFile()) {
return false;
}
String name = pathName.getName().toLowerCase(Locale.ENGLISH);
if (!name.startsWith(pattern)) {
return false;
}
if (!name.endsWith(format)) {
return false;
}
return true;
});
for (int i = 0; i < files.length; i++) {
File current = files[i];
if (current.isDirectory()) {
getFilesToProcess(result, current, pattern, format);
continue;
}
result.add(current);
}
}
public File[] getCustomerDirs(String sourcePath) {
File[] directories = new File(sourcePath).listFiles(File::isDirectory);
return directories;
}
}
I have not sure how I can write a filter maybe for example like this:
try (DirectoryStream<Path> stream = Files.newDirectoryStream(directoryPath, filter)) {
for (Path path : stream) {
if (Files.isRegularFile(path)) {
consumer.accept(path);
}
}
}
Here is a sample solution by my library: AbacusUtil
public List<File> getFilesToSend(String sourcePath, String pattern, String format) {
final Predicate<File> isTargetFile = f -> f.isFile()
&& N.startsWithIgnoreCase(f.getName(), pattern)
&& N.endsWithIgnoreCase(f.getName(), "." + format);
return Stream.list(new File(sourcePath))
.filter(File::isDirectory)
.map(f -> new File(f, "COB" + getPreviousWorkingDay()))
.flatMap(cobDir -> Stream.list(cobDir, true).filter(isTargetFile))
.toList();
}
I have return code to retrieve a list of all filepaths within a directory but I'm only getting the contents of the last folder. I have two folders, each has 3 files.
Here is my code:
import java.io.*;
import java.util.*;
class Filedirexts
{
public static void main(String[] args) throws IOException
{
String Dirpath = "E:/Share/tstlpatches";
String fieldirpath ="";
File file = new File(Dirpath);
List<String> strfilelst = new ArrayList<String>();
strfilelst = Filedirexts.getsubdir(file);
System.out.println(strfilelst.size());
for(int i=0;i<strfilelst.size();i++)
{
fieldirpath = strfilelst.get(i);
System.out.println("fieldirpath : "+fieldirpath);
}
}
public static List<String> getsubdir(File file) throws IOException
{
File[] filelist = file.listFiles();
List<String> strfileList = new ArrayList<String>();
System.out.println("filelist" + filelist.length);
for (int i=0; i< filelist.length ; i++)
{
if(filelist[i].exists())
{
if(filelist[i].isFile())
{
file = filelist[i];
System.out.println( " fileeach file : "+fileeach.getAbsolutePath());
strfileList.add(file.getAbsolutePath());
}
else if (filelist[i].isDirectory())
{
file = filelist[i];
System.out.println( " fileeach Directory : "+fileeach.getCanonicalPath());
strfileList = Filedirexts.getsubdir(file);
strfileList.add(file.getCanonicalPath().toString());
}
}
}
return strfileList;
}
}
This is my folder structure:
MainPath E:\Share\tstlpatches which is used in code itself
E:\Share\tstlpatches\BE
E:\Share\tstlpatches\BE\graphical
E:\Share\tstlpatches\BE\graphical\data1.txt
E:\Share\tstlpatches\BE\graphical\data2.txt
E:\Share\tstlpatches\BE\graphical\data3.txt
E:\Share\tstlpatches\BE\test
E:\Share\tstlpatches\BE\test\1.txt
E:\Share\tstlpatches\BE\test\2.txt
E:\Share\tstlpatches\BE\test\readme.txt
I'm only getting
E:\Share\tstlpatches\BE
E:\Share\tstlpatches\BE\test
E:\Share\tstlpatches\BE\test\1.txt
E:\Share\tstlpatches\BE\test\2.txt
E:\Share\tstlpatches\BE\test\readme.txt
If I use the normal method, it works fine, but when I use with the list I'm only getting the constents of the last folder.
What do I need to do to make the code work properly?
Your recursive method is incorrectly creating a new ArrayList<String> in each call and returning this new ArrayList in each invocation. This is why you are only seeing the contents of the last call.
Here's how to fix this:
1) Change the getsubdir to be void and pass in the List as a parameter.
public static void getsubdir(File file, List<String> strfileList) throws IOException
{
File[] filelist = file.listFiles();
System.out.println("filelist " + filelist.length);
for (int i=0; i< filelist.length ; i++)
{
if(filelist[i].exists())
{
if(filelist[i].isFile())
{
file = filelist[i];
System.out.println( " fileeach file : "+file.getAbsolutePath());
strfileList.add(file.getAbsolutePath());
}
else if (filelist[i].isDirectory())
{
file = filelist[i];
System.out.println( " fileeach Directory : "+file.getCanonicalPath());
// Note: Since you want the directory first in the list,
// add it before the recursive call
strfileList.add(file.getCanonicalPath().toString());
Filedirexts.getsubdir(file, strfileList);
}
}
}
}
2) Change the way you call it from main:
Instead of:
strfilelst = Filedirexts.getsubdir(file);
Just use:
Filedirexts.getsubdir(file, strfilelst);
In my project has 40 to 50 jar files available, It takes lot of time to find out latest version of each jar at every time. Can u any one help me to write a java program for this?
You may want to just use maven : http://maven.apache.org/
Or an other dependencies manager, like Ivy.
At the time of ant-build please call this method
public void ExpungeDuplicates(String filePath) {
Map<String,Integer> replaceJarsMap = null;
File folder = null;
File[] listOfFiles = null;
List<String> jarList = new ArrayList<String>();
String files = "";
File deleteFile = null;
Iterator<String> mapItr = null;
//String extension ="jar";
try {
folder = new File(filePath);
listOfFiles = folder.listFiles();
for (int i = 0; i < listOfFiles.length; i++) {
if (listOfFiles[i].isFile()) {
files = listOfFiles[i].getName();
jarList.add(files);
}
}
if (jarList.size() > 0) {
replaceJarsMap = PatternClassifier.findDuplicatesOrLowerVersion(jarList);
System.err.println("Duplicate / Lower Version - Total Count : "+replaceJarsMap.size());
mapItr = replaceJarsMap.keySet().iterator();
while (mapItr.hasNext()) {
String key = mapItr.next();
int repeat = replaceJarsMap.get(key);
System.out.println( key +" : "+repeat);
for (int i = 0; i <repeat; i++) {
deleteFile = new File(filePath + System.getProperty ("file.separator")+key);
try{
if (deleteFile != null && deleteFile.exists()){
if(deleteFile.delete()){
System.err.println(key +" deleted");
}
}
}catch (Exception e) {
}
}
}
}
} catch (Exception e) {
// TODO: handle exception
}
}
You only need to give the path of your Lib to this function.This method will find all the duplicate or lower version of of file.
And the crucial function is given below...Which finds out the duplicates from the list of files you provided.
public static Map<String,Integer> findDuplicatesOrLowerVersion(List<String> fileNameList) {
List<String> oldJarList = new ArrayList<String>();
String cmprTemp[] = null;
boolean match = false;
String regex = "",regexFileType = "",verInfo1 = "",verInfo2 = "",compareName = "",tempCompareName = "",tempJarName ="";
Map<String,Integer> duplicateEntryMap = new HashMap<String, Integer>();
int count = 0;
Collections.sort(fileNameList, Collections.reverseOrder());
try{
int size = fileNameList.size();
for(int i = 0;i<size;i++){
cmprTemp = fileNameList.get(i).split("[0-9\\._]*");
for(String s : cmprTemp){
compareName += s;
}
regex = "^"+compareName+"[ajr0-9_\\-\\.]*";
regexFileType = "[0-9a-zA-Z\\-\\._]*\\.jar$";
if( fileNameList.get(i).matches(regexFileType) && !oldJarList.contains(fileNameList.get(i))){
for(int j = i+1 ;j<size;j++){
cmprTemp = fileNameList.get(j).split("[0-9\\._]*");
for(String s : cmprTemp){
tempCompareName += s;
}
match = (fileNameList.get(j).matches(regexFileType) && tempCompareName.matches(regex));
if(match){
cmprTemp = fileNameList.get(i).split("[a-zA-Z\\-\\._]*");
for(String s : cmprTemp){
verInfo1 += s;
}
verInfo1 += "000";
cmprTemp = fileNameList.get(j).split("[a-zA-Z\\-\\._]*");
for(String s : cmprTemp){
verInfo2 += s;
}
verInfo2 += "000";
int length = 0;
if(verInfo1.length()>verInfo2.length()){
length = verInfo2.length();
}else{
length = verInfo1.length();
}
if(Long.parseLong(verInfo1.substring(0,length))>=Long.parseLong(verInfo2.substring(0,length))){
count = 0;
if(!oldJarList.contains(fileNameList.get(j))){
oldJarList.add(fileNameList.get(j));
duplicateEntryMap.put(fileNameList.get(j),++count);
}else{
count = duplicateEntryMap.get(fileNameList.get(j));
duplicateEntryMap.put(fileNameList.get(j),++count);
}
}else{
tempJarName = fileNameList.get(i);
}
match = false;verInfo1 = "";verInfo2 = "";
}
tempCompareName = "";
}
if(tempJarName!=null && !tempJarName.equals("")){
count = 0;
if(!oldJarList.contains(fileNameList.get(i))){
oldJarList.add(fileNameList.get(i));
duplicateEntryMap.put(fileNameList.get(i),++count);
}else{
count = dupl icateEntryMap.get(fileNameList.get(i));
duplicateEntryMap.put(fileNameList.get(i),++count);
}
tempJarName = "";
}
}
compareName = "";
}
}catch (Exception e) {
e.printStackTrace();
}
return duplicateEntryMap;
}
What findDuplicatesOrLowerVersion(List fileNameList) function task - Simply it found the duplicates and passting a map which contains the name of the file and number of time the lower version repeats.
Try this. The remaining file exist in the folder should be latest or files with out duplicates.Am using this for finding the oldest files.on the basis of that it will find the old and delete it.
This am only checking the name..Futher improvement you can made.
Where PatternClassifier is a class which contains the second method given here.