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“Java DateFormat is not threadsafe” what does this leads to?
Everybody cautions regarding Java DateFormat not being thread safe and I understand the concept theoretically.
11 Answers
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Dealing with “java.lang.OutOfMemoryError: PermGen space” error
...n going into the Tomcat/bin directory and running tomcat6w.exe. Under the "Java" tab, add the arguments to the "Java Options" box. Click "OK" and then restart the service.
If you get an error the specified service does not exist as an installed service you should run:
tomcat6w //ES//servicename
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What is the Java equivalent of PHP var_dump?
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It is not quite as baked-in in Java, so you don't get this for free. It is done with convention rather than language constructs. In all data transfer classes (and maybe even in all classes you write...), you should implement a sensible toString method. ...
Receiver not registered exception error?
... java.lang.RuntimeException: Unable to stop service com.google.android.exoplayer.demo.player.PlayService@141ba331: java.lang.IllegalArgumentException: Receiver not registered: com.google.android.exoplayer.demo.player.PlayServi...
Get type of a generic parameter in Java with reflection
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I get this exception : Exception in thread "main" java.lang.ClassCastException: java.lang.Class cannot be cast to java.lang.reflect.ParameterizedType not sure what is the constraint .
– Dish
Feb 29 '16 at 14:25
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Why java.lang.Object is not abstract? [duplicate]
Why is the Object class, which is base class of 'em all in Java, not abstract?
14 Answers
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java.lang.UnsupportedClassVersionError Unsupported major.minor version 51.0 [duplicate]
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java.lang.UnsupportedClassVersionError happens because of a higher JDK during compile time and lower JDK during runtime.
Here's the list of versions:
Java SE 9 = 53,
Java SE 8 = 52,
Java SE 7 = 51,
Java SE 6.0 = 50,
Java SE...
Which is more efficient, a for-each loop, or an iterator?
...ew for loop syntax, compare the generated bytecodes from the following two Java snippets. First the for loop:
List<Integer> a = new ArrayList<Integer>();
for (Integer integer : a)
{
integer.toString();
}
// Byte code
ALOAD 1
INVOKEINTERFACE java/util/List.iterator()Ljava/util/Itera...
How can I get the current stack trace in Java?
How do I get the current stack trace in Java, like how in .NET you can do Environment.StackTrace ?
21 Answers
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What does .class mean in Java?
What does .class mean in Java? For example, if I created a class called Print . What does Print.class return?
7 Answer...