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How to put Google Maps V2 on a Fragment using ViewPager
...ut_height="match_parent" />
</RelativeLayout>
Now, we code the Java class for showing the map in the file MapViewFragment.java:
public class MapViewFragment extends Fragment {
MapView mMapView;
private GoogleMap googleMap;
@Override
public View onCreateView(LayoutInfla...
How to extract a substring using regex
...
import java.util.regex.Matcher;
import java.util.regex.Pattern;
public class Test {
public static void main(String[] args) {
Pattern pattern = Pattern.compile(".*'([^']*)'.*");
String mydata = "some string with ...
Does setting Java objects to null do anything anymore?
I was browsing some old books and found a copy of "Practical Java" by Peter Hagger. In the performance section, there is a recommendation to set object references to null when no longer needed.
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Getting all names in an enum as a String[]
...ream(e.getEnumConstants()).map(Enum::name).toArray(String[]::new);
}
Pre Java 8 is still a one-liner, albeit less elegant:
public static String[] getNames(Class<? extends Enum<?>> e) {
return Arrays.toString(e.getEnumConstants()).replaceAll("^.|.$", "").split(", ");
}
That you w...
Difference between an application server and a servlet container?
...rvlet API (including JSP, JSTL).
An application server supports the whole JavaEE - EJB, JMS, CDI, JTA, the servlet API (including JSP, JSTL), etc.
It is possible to run most of the JavaEE technologies on a servlet-container, but you have to install a standalone implementation of the particular tec...
How to get the Full file path from URI
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Caused by: java.lang.IllegalArgumentException: URI is not absolute
– Anu Martin
Feb 15 '18 at 18:13
14
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What are five things you hate about your favorite language? [closed]
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Five things I hate about Java:
No first-class functions.
No type inference.
Lack of sane defaults in eg graphics.
NullPointerException not containing more information about what is null.
The proliferation of pointlessly "configurable" frameworks/se...
How to persist a property of type List in JPA?
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As mentioned in the comments below, the correct JPA 2 implementation is
javax.persistence.ElementCollection
@ElementCollection
Map<Key, Value> collection;
See: http://docs.oracle.com/javaee/6/api/javax/persistence/ElementCollection.html
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Why hasn't functional programming taken over yet?
...re longer. A Haskell program will almost always be more terse than, say, a Java program — even in a "bad fit" domain with lots of inherent state.
– Chuck
May 14 '10 at 17:17
29
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Filter Java Stream to 1 and only 1 element
I am trying to use Java 8 Stream s to find elements in a LinkedList . I want to guarantee, however, that there is one and only one match to the filter criteria.
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