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Understanding recursion [closed]
...A binary tree is a tree made of nodes that have exactly two children, typically called "left" and "right"; again the children can be nodes, or null. A root is a node that is not the child of any other node.
Imagine that a node, in addition to its children, has a value, a number, and imagine that we...
Reflection generic get field value
...field.get(objectInstance);
Another way, which is sometimes prefered, is calling the getter dynamically. example code:
public static Object runGetter(Field field, BaseValidationObject o)
{
// MZ: Find the correct method
for (Method method : o.getMethods())
{
if ((method.getName...
Why don't Java Generics support primitive types?
...nerics in Java are an entirely compile-time construct - the compiler turns all generic uses into casts to the right type. This is to maintain backwards compatibility with previous JVM runtimes.
This:
List<ClassA> list = new ArrayList<ClassA>();
list.add(new ClassA());
ClassA a = list.g...
Android - how do I investigate an ANR?
...ocking operations from within the event thread. You should make sure these all happen in separate threads. If nothing seems the problem, use DDMS and enable the thread view. This shows all the threads in your application similar to the trace you have. Reproduce the ANR, and refresh the main thread a...
How to get C# Enum description from value? [duplicate]
...ns.GetEnumDescription 's Enum value parameter to this Enum value and then call it like string description = ((MyEnum)value).GetEnumDescription()
– gkc
Nov 25 '14 at 14:09
...
Putting uncommitted changes at Master to a new branch by Git
...e1
git add deletedFile2
...
git commit -m "My Custom Message"
I am not really sure about the deleted files, but I guess they aren't included when you use git add .
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“[notice] child pid XXXX exit signal Segmentation fault (11)” in apache error.log [closed]
... Hmm thats weird. Can you make sure that the process that segfaults actually is the on you are attached gdb to? check dmesg for the pid of the segfaulted process.
– Mattias Wadman
Aug 19 '12 at 19:54
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No tests found with test runner 'JUnit 4'
...ng one of the test methods to start with "test..." (JUnit3 style) and then all tests are found. I renamed it back to what it was previously, and it still works.
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When to use a linked list over an array/array list?
...you know the number of elements in the array ahead of time so that you can allocate the correct amount of memory for the array
you need speed when iterating through all the elements in sequence. You can use pointer math on the array to access each element, whereas you need to lookup the node based...
postgresql return 0 if returned value is null
...ns the first of its arguments that is not null.
Null is returned only if all arguments are null. It is often
used to substitute a default value for null values when data is
retrieved for display.
Edit
Here's an example of COALESCE with your query:
SELECT AVG( price )
FROM(
SELECT *, cum...