creating array without declaring the size – java
Using Java.util.ArrayList or LinkedList is the usual way of doing this. With arrays that’s not possible as I know. Example:
java
What is the equivalent of Java’s System.out.println() in Javascript?
Essentially console.log(“Put a message here.”) if the browser has a supporting console. Another typical debugging method is using alerts, alert(“Put a message here.”) RE: Update II This seems to make sense, you are trying to automate QUnit tests, from what I have read on QUnit this is an in-browser unit testing suite/library. QUnit expects to … Read more
Difference between java.io.PrintWriter and java.io.BufferedWriter?
The API reference for BufferedWriter and PrintWriter detail the differences. The main reason to use the PrintWriter is to get access to the printXXX methods like println(). You can essentially use a PrintWriter to write to a file just like you would use System.out to write to the console. A BufferedWriter is an efficient way … Read more
How do the post increment (i++) and pre increment (++i) operators work in Java?
Does this help? The main point is that ++a increments the value and immediately returns it. a++ also increments the value (in the background) but returns unchanged value of the variable – what looks like it is executed later.
Exception in thread “AWT-EventQueue-0” java.lang.OutOfMemoryError: Java heap space
Java’s default heap size (at least last time I researched it) is 128 MB. The latest version of Eclipse (i.e. Helios) is set to run with a default heap size of 512 MB. (see the eclipse.ini file in your Eclipse base path). Therefore, you are probably seeing this behavior because your application needs a heap … Read more
While else statement equivalent for Java?
The closest Java equivalent is to explicitly keep track of whether you exited the loop with a break… but you don’t actually have a break in your code, so using a while-else was pointless in the first place. For Java folks (and Python folks) who don’t know what Python’s while-else does, an else clause on a while loop executes if the loop ends without … Read more
Convert float to double without losing precision
It’s not that you’re actually getting extra precision – it’s that the float didn’t accurately represent the number you were aiming for originally. The double is representing the original float accurately; toString is showing the “extra” data which was already present. For example (and these numbers aren’t right, I’m just making things up) suppose you … Read more
Read next word in java
You do not necessarily have to split the line because java.util.Scanner’s default delimiter is whitespace. You can just create a new Scanner object within your while statement.
Java regex email
FWIW, here is the Java code we use to validate email addresses. The Regexp’s are very similar: Works fairly reliably.
Could not transfer artifact org.apache.maven.plugins:maven-surefire-plugin:pom:2.7.1 from/to central (http://repo1.maven.org/maven2)
Simplify things by using the following settings.xml: Under Linux/Unix, place it under ~/.m2/settings.xml. Under Windows place it under c:\documents and settings\youruser\.m2\settings.xml or c:\users\youruser\.m2\settings.xml. You don’t need the <mirrors/>, <profiles/> and <settings/> sections, unless you really know what they’re for.