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when hs_err_pidxxxx.log will generate?

public class Crash {
public static void main(String[] args) {
System.exit(0);
}
}
How to crash the JVM so it will generate the hs_err_pidxxxx.log

The log file is located in the "current directory" of the process by default. This can changed - see It is posible to write hs_err_pid*.log in a specific directory (different than the class directory) when java virtual machine crash?.

How to get path to class file in eclipse and linux in java?

In eclipse for windows, when I run
public class HelloWorld {
public static void main(String[] args) {
System.out.println(System.getProperty("user.dir"));
}
}
It gives me the path of the project root folder (which contains the bin folder which has the class file). For example
SampleProject
and the class file is actually located at
SampleProject\bin\myclass.class
But if I run the same program in linux with
javac myclass.java
java myclass
it gives me the directory that has the .class file, which is the same as pwd command. This is what I want in eclipse for windows. I want some code that will give me the path to the class file in both eclipse for windows and linux.
Does anyone know how do this?
Thanks

If I understand you correctly, you'd like a method that retrieves a class' path on disk. This is easily achievable, like so:
public String getClassPath(Class c) {
try {
return c.getProtectionDomain().getCodeSource().getLocation().toURI().getPath();
} catch (URISyntaxException e) {
e.printStackTrace();
}
return null;
}
NOTE this will work even if the class is contained in a jar file. It will return the path to the jar in this case.

The easiest way is to do this:
public class HelloWorld {
public static void main(String[] args) {
System.out.println(HelloWorld.class.getResource("HelloWorld.class"));
}
}

Java opening File Streams in one class and closing/deletion of file in another class

I want to delete the file which is opened and done writing but not closed. Please refer to code below:
Class A (can't be changed):
import java.io.FileOutputStream;
public class A {
public void run(String file) throws Exception {
FileOutputStream s = new FileOutputStream(file);
}
}
Class B:
import java.io.File;
import java.nio.file.Files;
import java.nio.file.Paths;
public class B {
public static void main(String[] args) throws Exception {
String path = "D:\\CONFLUX_HOME\\TestClient\\Maps\\test\\newTest.txt";
A a = new A();
a.run(path);
File f = new File(path);
Files.delete(Paths.get(f.getAbsolutePath()));
}
}
In Class A , just open the stream without closing the file.
In class B , calling A's run method and then try to delete the file.
Since the file is still opened. I'm unable to delete the file.
Error is :
The process cannot access the file because it is being used by another process.
Actual Scenario is :
We are loading the jars dynamically. Classes inside jar are creating the file. When there is an exception, a file gets created whose size will be 0 bytes. We need to delete this file. Since the file is not closed during the exception, we can't delete the file.
We could fix the issue if we could close the streams in the jar classes, but we can't modify the jars that create the files as they are client specific jars.
Please suggest how to delete the opened file, without modifying the code in class A.

Make sure you close the file, even if there was an Exception when writing to it.
E.g.
public void run(String file) throws Exception {
FileOutputStream s = null;
try {
s = new FileOutputStream(file);
} finally {
try {
s.close();
} catch(Exception e) {
// log this exception
}
}
}

You have to close the file before any delete operation as firstly its a bad practice and second is it will lead to memory leaks.

If you are using Tomcat, it is possible to set AntiLockingOption and antiJARLocking in $CATALINA_HOME/conf/context.xml for Windows:
<Context antiJARLocking="true" antiResourceLocking="true" >
Important note:
The antiResourceLocking option can stop JSPs from redeploying when they are edited requiring a redeploy.
Read more about this option:
http://tomcat.apache.org/tomcat-7.0-doc/config/context.html
antiResourceLocking:
If true, Tomcat will prevent any file locking. This will significantly impact startup time of applications, but allows full webapp hot deploy and undeploy on platforms or configurations where file locking can occur. If not specified, the default value is false.

Pass the resource as a parameter and it becomes the caller's responsibility to clear up the resources
public void run(FileOutputStream stream) throws Exception {
...
}
caller:
try(FileStream stream = new FileStream(path)){
A a = new A();
a.run(stream);
}catch(Exception e){
.. exception handling
}

Updated according to OPs comment.
Another approach could be to subclass A and override run().
public static void main(String[] args) throws Exception {
String path = "D:\\CONFLUX_HOME\\TestClient\\Maps\\test\\newTest.txt";
A a = new A() {
#Override
public void run(String file) throws Exception {
FileOutputStream s = new FileOutputStream(file);
s.close();
}
};
a.run(path);
File f = new File(path);
Files.delete(Paths.get(f.getAbsolutePath()));
System.out.println("foo");
}

I don't think you'll find a pure java solution to this problem. One option is to install Unlocker (being careful to hit "Skip" on all the junkware) and invoke it from your code.
If you have UAC enabled, you'll also need to be running your java in an elevated process (e.g. start command prompt as Administrator). Then, assuming unlocker is in C:\Program Files\Unlocker:
Process p = new ProcessBuilder("c:\\Program Files\\Unlocker\\Unlocker.exe",path,"-s").start();
p.waitFor();
And after that you can delete the file as before. Or you could use "-d" instead of "-s" and Unlocker will delete the file for you.

Mule - testing a flow that has an inbound/outbound endpoint with a Mule property as the file path

I'm trying to write a test for a Mule flow that will involve dropping a file in a location, waiting for it to be processed by my flow and compare the output to see if it has been transformed correctly. My flow looks as follows:
<flow name="mainFlow" processingStrategy="synchronous">
<file:inbound-endpoint name="fileIn" path="${inboundPath}">
<file:filename-regex-filter pattern="myFile.csv" caseSensitive="true"/>
</file:inbound-endpoint>
...
<file:outbound-endpoint path="${outboundPath}" outputPattern="out.csv"/>
</flow>
Is there a way I can access the inboundPath and outboundPath Mule properties inside of my test class so that I can drop files and wait for output in the correct places?
The test class I'm using is:
public class MappingTest extends BaseFileToFileFunctionalTest {
#Override
protected String getConfigResources() {
return "mappingtest.xml";
}
#Test
public void testMapping() throws Exception {
dropInputFileIntoPlace("myFile.csv");
waitForOutputFile("out.csv", 100);
assertEquals(getExpectedOutputFile("expected-out.csv"), getActualOutputFile("out.csv"));
}
}
Which extends this class:
public abstract class BaseFileToFileFunctionalTest extends FunctionalTestCase {
private static final File INPUT_DIR = new File("/tmp/muletest/input");
private static final File OUTPUT_DIR = new File("/tmp/muletest/output");
private static final Charset CHARSET = Charsets.UTF_8;
#Before
public void setup() {
new File("/tmp/muletest/input").mkdirs();
new File("/tmp/muletest/output").mkdirs();
empty(INPUT_DIR);
empty(OUTPUT_DIR);
}
private void empty(File inputDir) {
for (File file : inputDir.listFiles()) {
file.delete();
}
}
protected File waitForOutputFile(String expectedFileName, int retryAttempts) throws InterruptedException {
boolean polling = true;
int attemptsRemaining = retryAttempts;
File outputFile = new File(OUTPUT_DIR, expectedFileName);
while (polling) {
Thread.sleep(100L);
if (outputFile.exists()) {
polling = false;
}
if (attemptsRemaining == 0) {
VisibleAssertions.fail("Output file did not appear within expected time");
}
attemptsRemaining--;
}
outputFile.deleteOnExit();
return outputFile;
}
protected void dropInputFileIntoPlace(String inputFileResourceName) throws IOException {
File inputFile = new File(INPUT_DIR, inputFileResourceName);
Files.copy(Resources.newInputStreamSupplier(Resources.getResource(inputFileResourceName)), inputFile);
inputFile.deleteOnExit();
}
protected String getActualOutputFile(String outputFileName) throws IOException {
File outputFile = new File(OUTPUT_DIR, outputFileName);
return Files.toString(outputFile, CHARSET);
}
protected String getExpectedOutputFile(String resourceName) throws IOException {
return Resources.toString(Resources.getResource(resourceName), CHARSET);
}
}
As you can see I'm currently creating temporary input/output directories. I'd like to make this part read from the Mule properties if possible? Thanks in advance.

After observing your test classes and code I could see that you want to dynamically create temp folders place files in them. And the flow should read the files from Temp Directory and write output to another Temp directory. Point to be noted is that Mule's Endpoints are created when the configuration is loaded. So the ${inbound} and ${outbound} should be provided to the mule flow by the time they are provided.
So one option can be to create a dummy flow pointing to the temp folders for testing.
or
Create a test properties file pointing to the temp folders and load that to your flow config, so that your flow endpoints will get the temp folder paths.
In any way path cannot be provided to the flow inbound endpoints after they have been created(on config load).
Update1:
As per your comment the solution with option would be like the following.
Seperate the properties loading part of the config into another config.
Like "mapping-core-config.xml,mappingtest.xml" where the mapping-core-config will have the tags to load the properties file.
Now create a test config file for the mapping-core-config.xml file which loads the test properties file. This should be used in your test config. This way without modifying or disturbing your main code, you can test your flows pointing to temp folders.
"mapping-core-test-config.xml,mappingtest.xml"
Note: The test config can reside in the src/test/resources folders.
Hope this helps.

Serving static content with grizzly's StaticHttpHandler from within a .jar

I want Grizzly to serve static files from within a .jar, which contains a JAX-RS application, Grizzly and all other libs. I'm using org.glassfish.grizzly.http.server.StaticHttpHandler to serve the static files.
public class Main {
// ...
public static void main(String[] args) throws IOException, URISyntaxException {
final HttpServer server = startServer();
server.getServerConfiguration().addHttpHandler(
new StaticHttpHandler(getTemplatePath()), "/static");
System.in.read();
server.stop();
}
private static String getTemplatePath() throws URISyntaxException {
return Main.class.getClassLoader().getResource("templates/static").getPath();
}
}
But it works only, if I start the application with my IDE. If I pack a .jar and run it, the static files are not found.
Is it possible to serve static files from within a .jar with grizzly's StaticHttpHandler? And how?

You have to use CLStaticHttpHandler instead of StaticHttpHandler.
Please take a look at this question
html server grizzly+jersey (.html from .jar archive)