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How to read attributes using XML apache commons configuration

java,xml,xml-parsing,apache-commons
I am using Apache Commons Configuration for reading configuration in xml file - standalone-full-ha.xml in Wildfly 8 application server. <?xml version="1.0" ?> <server xmlns="urn:jboss:domain:2.2"> ... ... <profile> ... ... <subsystem xmlns="urn:jboss:domain:datasources:2.0"> <datasources> <datasource jta="true" jndi-name="java:/TestDB" pool-name="TestDB" enabled="true" use-java-context="true" spy="false" use-ccm="true"> <connection-url>jdbc:sybase:Tds:ip:port/db-name</connection-url> ......

How to notify thread of changes

java,apache-commons,notify
I have created a class FolderObserver which observes a folder in my project for changes (file created/file deleted). My class is implementing the Runnable interface (I'm using the classes FileAlterationObserver, FileAlterationMonitor, FileAlterationListener from apache commons). In my main class I start a thread with my FolderObserver object as an argument....

How to save xml configuration filled with values from properties file in Apache Commons Configuration can't save

java,xml,groovy,apache-commons,apache-commons-config
I am trying to use Apache Commons Configuration in groovy script to read values from a simple properties file and fill an XML template with these values from that file. The goal of this example is to be able to launch multiple instances of Tomcat with settings defined in properties...

How to check for empty String array including empty elements

java,arrays,apache-commons
org.apache.commons.lang3.ArrayUtils provides methods to check if Array is empty, but for example for String array which has empty String elementsmeaning character "" it returns true for that isNotEmpty() method, which is correct as that method check only for null and length == 0. Is there any other method or implementation...

Best way to return null from a method?

java,guava,apache-commons
I need to get the hostname of the machine where the code is running. I have a method like this: private static final String getHostName() { try { return InetAddress.getLocalHost().getCanonicalHostName().toLowerCase(); } catch (UnknownHostException ex) { logger.logError("error = ", ex); } // this looks pretty odd to me, are there any...

Apache Commons Lang HashCodeBuilder collision

java,hash,apache-commons,hash-collision,apache-commons-lang
I am getting collision with using Apache Commons Lang HashCodeBuilder using release 3.4. I am hashing a Route object, which contains two Cell objects, start and end. At the end I am providing an example when collision occurs. Both classes override hashCode and equals method. First the Cell class: import...

Mail doesn't get sent out using Apache Commons Mail

java,javamail,apache-commons,apache-commons-email
I'm using version 1.3.3 Apache Commons Mail for sending out emails. I've tried changing the Apache mail version using telnet smtp.gmail.com 587 to test for connectivity (it works, so its not about the firewall) trying out with different ports setting SSL/ TSL and tried other bunch of methods configured my...

format a String by a notation

java,slf4j,apache-commons
I have a string such as following: Filed Id is invalid, value = {} and valid ranges = '{},{},{}' and I want replace {} by custom value in runtime. I see this pattern in SLF4J and real question is : Is there a third party utility for support this requirement...

Package does not exist when compiling

java,linux,import,apache-commons
I´ve made a Java Project on Windows and now I want to use it under Linux. Since I am working with Files, I "need" the org.apache.commons.io.FilenameUtils package. Under Windows I am working with IntelliJ, so it manages everything for me. I am sharing the Directory of the Project via VirtualBox...

How does Apache commons IO convert my XML header from UTF-8 to UTF-16?

java,utf-8,apache-commons,utf-16,document-conversion
I’m using Java 6. I have an XML template, which begins like so <?xml version="1.0" encoding="UTF-8"?> However, I notice when I parse and output it with the following code (using Apache Commons-io 2.4) … Document doc = null; InputStream in = this.getClass().getClassLoader().getResourceAsStream(“my-template.xml”); try { byte[] data = org.apache.commons.io.IOUtils.toByteArray( in );...

Error: Server Error while uploading file to mysql using org.apache.commons.upload

google-app-engine,apache-commons
I am trying to upload a word doc file in MySQL database in a Google app engine application. I am using org.apache.commons.upload to upload file.i have tried so many variations in my code but it every time it gives me same error. Error: Server Error The server encountered an error...

Preconditions library to throw IllegalArgumentException for notNull check

java,nullpointerexception,guava,apache-commons,preconditions
Do you know some nice alternative to Apache Commons Validate or Guava Preconditions that would throw IllegalArgumentException instead of NullPointerException when checking if object is not null (except Spring Assert)? I'm aware that Javadocs say: Applications should throw instances of this class [NullPointerException] to indicate other illegal uses of the...

org.apache.commons.httpclient.HttpClient multithreading calls crash

apache,apache-commons,apache-commons-httpclient
Hi all I use apache's httpclient to make restcalls, everything is working fine, When multiple thread are using this method my app crashes. What is the implementation for this class that is MultithreadSafe. Here is my code. httpClient = new HttpClient(); HttpMethod method = null; method = new GetMethod(); ......

Getting HTTP 302 when downloading file in Java using Apache Commons

java,file,url,apache-commons,fileutils
I am using the following method to download a file off the internet: try { URL url = new URL("http://search.maven.org/remotecontent?filepath=com/cedarsoftware/json-io/4.0.0/json-io-4.0.0.jar"); FileUtils.copyURLToFile(url, new File(jsonerFolder.getParent() + "\\mods\\json-io-4.0.0.jar")); } catch (Exception e1) { logger.error("Downloading json-io failed with an exception"); e1.printStackTrace(); } But the downloaded file is not a jar, rather, it is an...

How can I sort a List of Pair?

java,apache-commons
I have a list of commmons Pair that stores words and their frequency like the following private List<Pair<String, Integer>> words = new ArrayList<Pair<String, Integer>(); I am trying to sort it so that when I iterate over it to print the words, I want the words with the highest frequency to...

What is the difference between maxTotal and maxIdle in Apache Commons Pool 2?

java,apache,apache-commons,pool
I'm using the Apache Commons Pool 2 implementation to have object pool mechanism for my application. As of now, I have set the default value of maxTotal() and maxIdle() as 10 in my code. But I am not able to understand what is the difference between them ? What if...

Multipart Request and Custom Header

java,file-upload,apache-commons
For my current solution, I'm using apache commons FileUpload library to process incoming multi-part requests. I'm able to send the files appropriately then read the stream on the server end using the streaming api code here. If you look at the format of multipart requests listed here, there is a...

Does `org.apache.commons.math3.distribution.BinomialDistribution(1,p)` come with much performance overhead?

java,apache-commons,apache-commons-math,bernoulli-probability
A Bernoulli distribution is equivalent to a binomial distribution with only 1 trial i.e. BinomialDistribution(1,p) from the Apache Commons Math library. A Bernoulli distribution is obviously a much simpler thing than the general binomial distribution. If performance matters, should I roll my own BernoulliDistribution(p) by subclassing AbstractIntegerDistribution, or would I...

Adding new libraries to java [duplicate]

java,apache-commons
This question already has an answer here: Setting multiple jars in java classpath 20 answers I am trying to use a feature from the Apache Commons called StringUtils. However this requires you download the libary and add it so I can use the code import org.apache.commons.lang3.StringUtils;. My problem is...

Apache Commons FTP not writing to FileOutputStream with no error thrown

android,ftp,apache-commons
I am using the apache commons library in an android app that we have developed. This is legacy code, and for some reason, it is not writing to the device. This is happening on multiple devices, so it's not device specific. We are using Nexus 7 devices running Android 4.4....

java.lang.IllegalArgumentException: 'hello' does not contain an equals sign

java,apache-commons,properties-file
I am currently using the Apache commons configuration library to write and read data from a file. I am able to save the key value pair colors=hello to the user..properties file, but when i try to read the value is get the below exception. Exception in thread "main" java.lang.IllegalArgumentException: 'hello'...

How to parse configuration files in xml using apache commons?

java,xml,xml-parsing,apache-commons
I am using apache commons configuration 1.10 to manage xml configurations. This is a configuration file in xml format. <?xml version="1.0" encoding="ISO-8859-1" ?> <config> <mainServerHostname>MainServer</mainServerHostname> <failoverServers> <server> <ipAddress>192.168.0.5</ipAddress> <priority>1</priority> </server> <server> <ipAddress>192.168.0.6</ipAddress> <priority>2</priority> </server> </failoverServers>...

unable to resolve class org.apache.commons.net.ftp in grails

grails,apache-commons
I am developing a module in which some file need to be uploaded on a ftp server for that I have added the "commons-net-3.3.jar" in my grails app & while using it import org.apache.commons.net.ftp.FTP import org.apache.commons.net.ftp.FTPClient import org.apache.commons.net.ftp.FTPClientConfig import org.apache.commons.net.ftp.FTPFile import org.apache.commons.net.ftp.FTPReply It is throwing the error unable to resolve...

How to validate certain input parameters through a Validation API?

java,validation,apache-commons
I have an API in which I am doing my own validation for certain input parameters. For example - public Builder(int clientId) { TestUtils.assertNonNegative(clientId, "ClientId"); this.clientId = clientId; } public Builder setUserId(String userid) { TestUtils.assertNotNull(userid, "UserId"); this.userid = userid; return this; } And my assertNonNegative and assertNotNull method in TestUtils...