I am reading in a file in Java and when I use the absolute path it works fine.
File myObj = new File("/Users/aaronmk2/Downloads/demo2/SystemDependencies/src/sample_input.txt");
However, when I try to use the relative path I get a No such file or directory error
File myObj = new File("../sample_input.txt");
When I use my terminal and use nano ../sample_input.txt it opens up the file.
What do I need to add to get the relative path to work?
Java does relative paths just fine. Clearly, then, the 'current working directory' for your java process is not the same as the cwd when you're invoking nano.
You can check the CWD in java. Either way will work:
System.out.println(new File(".").getAbsolutePath());
or:
System.out.println(System.getProperty("user.dir"));
You should find that it is different. The 'cwd' for a java process is the cwd that it was set to by whatever started java. If you're invoking java from the command line, it'll be the directory you're in as you do so. If you are double clicking a jar, it'll be the directory the jar is in. If you're making a windows shortcut, it's the directory listed in the shortcut. Example:
cd /foo/bar
java -jar /bar/baz/hello.jar
In the above example, the cwd is /foo/bar. Not /bar/baz.
I'm trying to install hadoop on my computer (Windows 10, 64 bit) but when I go to test if it installed, I keep getting the error:
'-classpath' is not recognized as an internal or external command,
operable program or batch file.
I have no idea why this is happening. I thought my system variables were set correctly but apparently not. I was just wondering if anyone could tell me what is going on with this -classpath stuff. Below is a snapshot of the error
enter image description here
And here are further images of my stem and path variables. As well as a snapshot of the bin directory in hadoop.
enter image description here
enter image description here
For me the problem was that %JAVA_HOME% included a space in the path C:\Program Files\Java\jdk1.8.0_191. After changing it to C:\Progra~1\Java\jdk1.8.0_191 it started to work.
So check that all the relevant env variables (Java, Hadoop) are defined without spaces.
You have problem with your path . Your path contains some spaces. Just remove the spaces .
Suppose any folder name in your path is like
Hadoop folder
You can clearly see the space in your folder name in your path so you just rename the folder name as
Hadoopfolder
Or
Hadoop-folder
Just rename it everywhere and try to install it again .
I have a path in windows as:
C:\\Users\\Sneha\\.netbeans\\5.5.1\\tomcat55.properties
How can we convert the above path to Linux path. what does .netbeans and tomcat55.properties path means.
Any help would be appreciated.
you should read this webpage to understand difference between file system in linux and windows.
to convert that windows path to linux path, you must know that names of directories and files are case sensitive in linux,
then except using C:\\Users\\Sneha use this method in java to get current user path in any machine(windows, linux and etc.)
String user_dir = System.getProperty("user.home");
then in linux, path contains only forward slash /. not backward slash \.
so the path you said
C:\Users\Sneha\.netbeans\5.5.1\tomcat55.properties
will be
/home/Sneha/.netbeans/5.5.1/tomcat55.properties
also
.netbeans is a folder,
tomcat55.properties is a file.
I've recently searched how I could get the application's directory in Java. I've finally found the answer but I've needed surprisingly long because searching for such a generic term isn't easy. I think it would be a good idea to compile a list of how to achieve this in multiple languages.
Feel free to up/downvote if you (don't) like the idea and please contribute if you like it.
Clarification:
There's a fine distinction between the directory that contains the executable file and the current working directory (given by pwd under Unix). I was originally interested in the former but feel free to post methods for determining the latter as well (clarifying which one you mean).
In Java the calls
System.getProperty("user.dir")
and
new java.io.File(".").getAbsolutePath();
return the current working directory.
The call to
getClass().getProtectionDomain().getCodeSource().getLocation().getPath();
returns the path to the JAR file containing the current class, or the CLASSPATH element (path) that yielded the current class if you're running directly from the filesystem.
Example:
Your application is located at
C:\MyJar.jar
Open the shell (cmd.exe) and cd to C:\test\subdirectory.
Start the application using the command java -jar C:\MyJar.jar.
The first two calls return 'C:\test\subdirectory'; the third call returns 'C:\MyJar.jar'.
When running from a filesystem rather than a JAR file, the result will be the path to the root of the generated class files, for instance
c:\eclipse\workspaces\YourProject\bin\
The path does not include the package directories for the generated class files.
A complete example to get the application directory without .jar file name, or the corresponding path to the class files if running directly from the filesystem (e.g. when debugging):
String applicationDir = getClass().getProtectionDomain().getCodeSource().getLocation().getPath();
if (applicationDir.endsWith(".jar"))
{
applicationDir = new File(applicationDir).getParent();
}
// else we already have the correct answer
In .NET (C#, VB, …), you can query the current Assembly instance for its Location. However, this has the executable's file name appended. The following code sanitizes the path (using System.IO and using System.Reflection):
Directory.GetParent(Assembly.GetExecutingAssembly().Location)
Alternatively, you can use the information provided by AppDomain to search for referenced assemblies:
System.AppDomain.CurrentDomain.BaseDirectory
VB allows another shortcut via the My namespace:
My.Application.Info.DirectoryPath
In Windows, use the WinAPI function GetModuleFileName(). Pass in NULL for the module handle to get the path for the current module.
Python
path = os.path.dirname(__file__)
That gets the path of the current module.
Objective-C Cocoa (Mac OS X, I don't know for iPhone specificities):
NSString * applicationPath = [[NSBundle mainBundle] bundlePath];
In Java, there are two ways to find the application's path. One is to employ System.getProperty:
System.getProperty("user.dir");
Another possibility is the use of java.io.File:
new java.io.File("").getAbsolutePath();
Yet another possibilty uses reflection:
getClass().getProtectionDomain().getCodeSource().getLocation().getPath();
In VB6, you can get the application path using the App.Path property.
Note that this will not have a trailing \ EXCEPT when the application is in the root of the drive.
In the IDE:
?App.Path
C:\Program Files\Microsoft Visual Studio\VB98
In .Net you can use
System.IO.Directory.GetCurrentDirectory
to get the current working directory of the application, and in VB.NET specifically you can use
My.Application.Info.DirectoryPath
to get the directory of the exe.
Delphi
In Windows applications:
Unit Forms;
path := ExtractFilePath(Application.ExeName);
In console applications:
Independent of language, the first command line parameter is the fully qualified executable name:
Unit System;
path := ExtractFilePath(ParamStr(0));
Libc
In *nix type environment (also Cygwin in Windows):
#include <unistd.h>
char *getcwd(char *buf, size_t size);
char *getwd(char *buf); //deprecated
char *get_current_dir_name(void);
See man page
Unix
In unix one can find the path to the executable that was started using the environment variables. It is not necessarily an absolute path, so you would need to combine the current working directory (in the shell: pwd) and/or PATH variable with the value of the 0'th element of the environment.
The value is limited in unix though, as the executable can for example be called through a symbolic link, and only the initial link is used for the environment variable. In general applications on unix are not very robust if they use this for any interesting thing (such as loading resources). On unix, it is common to use hard-coded locations for things, for example a configuration file in /etc where the resource locations are specified.
In bash, the 'pwd' command returns the current working directory.
In PHP :
<?php
echo __DIR__; //same as dirname(__FILE__). will return the directory of the running script
echo $_SERVER["DOCUMENT_ROOT"]; // will return the document root directory under which the current script is executing, as defined in the server's configuration file.
echo getcwd(); //will return the current working directory (it may differ from the current script location).
?>
in Android its
getApplicationInfo().dataDir;
to get SD card, I use
Environment.getExternalStorageDirectory();
Environment.getExternalStoragePublicDirectory(String type);
where the latter is used to store a specific type of file (Audio / Movies etc). You have constants for these strings in Environment class.
Basically, for anything to with app use ApplicationInfo class and for anything to do with data in SD card / External Directory using Environment class.
Docs :
ApplicationInfo ,
Environment
In Tcl
Path of current script:
set path [info script]
Tcl shell path:
set path [info nameofexecutable]
If you need the directory of any of these, do:
set dir [file dirname $path]
Get current (working) directory:
set dir [pwd]
Java:
On all systems (Windows, Linux, Mac OS X) works for me only this:
public static File getApplicationDir()
{
URL url = ClassLoader.getSystemClassLoader().getResource(".");
File applicationDir = null;
try {
applicationDir = new File(url.toURI());
} catch(URISyntaxException e) {
applicationDir = new File(url.getPath());
}
return applicationDir;
}
in Ruby, the following snippet returns the path of the current source file:
path = File.dirname(__FILE__)
In CFML there are two functions for accessing the path of a script:
getBaseTemplatePath()
getCurrentTemplatePath()
Calling getBaseTemplatePath returns the path of the 'base' script - i.e. the one that was requested by the web server.
Calling getCurrentTemplatePath returns the path of the current script - i.e. the one that is currently executing.
Both paths are absolute and contain the full directory+filename of the script.
To determine just the directory, use the function getDirectoryFromPath( ... ) on the results.
So, to determine the directory location of an application, you could do:
<cfset Application.Paths.Root = getDirectoryFromPath( getCurrentTemplatePath() ) />
Inside of the onApplicationStart event for your Application.cfc
To determine the path where the app server running your CFML engine is at, you can access shell commands with cfexecute, so (bearing in mind above discussions on pwd/etc) you can do:
Unix:
<cfexecute name="pwd"/>
for Windows, create a pwd.bat containing text #cd, then:
<cfexecute name="C:\docume~1\myuser\pwd.bat"/>
(Use the variable attribute of cfexecute to store the value instead of outputting to screen.)
In cmd (the Microsoft command line shell)
You can get the name of the script with %* (may be relative to pwd)
This gets directory of script:
set oldpwd=%cd%
cd %0\..
set app_dir=%pwd%
cd %oldpwd%
If you find any bugs, which you will. Then please fix or comment.
I released https://github.com/gpakosz/whereami which solves the problem in C and gives you:
the path to the current executable
the path to the current module (differs from path to executable when calling from a shared library).
It uses GetModuleFileNameW on Windows, parses /proc/self/maps on Linux and Android and uses _NSGetExecutablePath or dladdr on Mac and iOS.
Note to answer "20 above regarding Mac OSX only: If a JAR executable is transformed to an "app" via the OSX JAR BUNDLER, then the getClass().getProtectionDomain().getCodeSource().getLocation(); will NOT return the current directory of the app, but will add the internal directory structure of the app to the response. This internal structure of an app is /theCurrentFolderWhereTheAppReside/Contents/Resources/Java/yourfile
Perhaps this is a little bug in Java. Anyway, one must use method one or two to get the correct answer, and both will deliver the correct answer even if the app is started e.g. via a shortcut located in a different folder or on the desktop.
carl
SoundPimp.com
I am trying to run the command:
cmd.exe /X /C "svn --non-interactive info <file name>
by using commandline.class from the API (org.codehaus.plexus.util.cli) which is called by
SVNInfoCommand.class(org.apache.maven.scm.provider.svn.svnexe.command.info)
It works fine when I pass a filename which exists in C:\ drive.
But it returns the following error when I pass a filename which exists in shared location or network drive. Error: "UNC paths are not supported. Defaulting to Windows directory. svn: '.' is not a working copy"
Current working directory is being set using the method setWorkingDirectory( String path ), but I suspect working directory is not being set when we use shared locations(UNC Paths).
EX: \Test_Location\Test_File
This command works fine when I pass the “absolute path” of filename located in shared drive.
(\Test_Location\Test_File)
Please let me know why we get this error when we use UNC paths even after setting the working directory.
By default, the Windows command processor (cmd.exe) doesn't support UNC paths.
You can alter this behavior by adding a dedicated registry key, as described in Microsoft KB 156276.
Alternatively, you can map your UNC path to a standard drive letter, and then use that.