60
votes
30
answers
1.3K
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Why use getters and setters/accessors?
What's the advantage of using getters and setters - that only get and set - instead of simply using publi
64
votes
30
answers
836
views
How can I avoid Java code in JSP files, using JSP 2?
I'm new to Java EE and I know that something like the following three lines <%= x+1 %> <%= reque
51
votes
30
answers
705
views
Sort a Map<Key, Value> by values
I am relatively new to Java, and often find that I need to sort a Map<Key, Value> on the values. Since
51
votes
30
answers
1.1K
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How to split a string in Java
I have a string, "004-034556", that I want to split into two strings: string1="004"; string2="034556"; That
54
votes
15
answers
2.8K
views
Why does this code using random strings print "hello world"?
The following print statement would print "hello world". Could anyone explain this? System.out.println(random
63
votes
30
answers
2.2K
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How to generate a random alpha-numeric string
I've been looking for a simple Java algorithm to generate a pseudo-random alpha-numeric string. In my si
66
votes
25
answers
567
views
Does Java support default parameter values?
I came across some Java code that had the following structure: public MyParameterizedFunction(String param1,
57
votes
27
answers
1.4K
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Java inner class and static nested class
What is the main difference between an inner class and a static nested class in Java? Does design / implementa
66
votes
11
answers
911
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How to use java.net.URLConnection to fire and handle HTTP requests
Use of java.net.URLConnection is asked about pretty often here, and the Oracle tutorial is too concise about i
62
votes
23
answers
411
views
What is a JavaBean exactly?
I understood, I think, that a "Bean" is a Java class with properties and getters/setters. As much as I underst
63
votes
30
answers
1.7K
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How do you assert that a certain exception is thrown in JUnit 4 tests?
How can I use JUnit4 idiomatically to test that some code throws an exception? While I can certainly do somet
59
votes
30
answers
1.1K
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What's the simplest way to print a Java array?
In Java, arrays don't override toString(), so if you try to print one directly, you get the className + &
57
votes
30
answers
1.8K
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"implements Runnable" vs "extends Thread" in Java
From what time I've spent with threads in Java, I've found these two ways to write threads: With imp
65
votes
28
answers
2.1K
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54
votes
29
answers
2.6K
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What's the difference between @Component, @Repository & @Service annotations in Spring?
Can @Component, @Repository and @Service annotations be used interchangeably in Spring or do they provide any
53
votes
22
answers
1.2K
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What is reflection and why is it useful?
What is reflection, and why is it useful? I'm particularly interested in Java, but I assume the principle
54
votes
23
answers
2.1K
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How do I call one constructor from another in Java?
Is it possible to call a constructor from another (within the same class, not from a subclass)? If yes how? An
54
votes
29
answers
2.9K
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How do I determine whether an array contains a particular value in Java?
I have a String[] with values like so: public static final String[] VALUES = new String[] {"AB","BC","CD","AE
47
votes
30
answers
757
views
Does a finally block always get executed in Java?
Considering this code, can I be absolutely sure that the finally block always executes, no matter what somethi
55
votes
30
answers
1.9K
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How can I fix 'android.os.NetworkOnMainThreadException'?
I got an error while running my Android project for RssReader. Code: URL url = new URL(urlToRssFeed); SAXPa