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Short form for Java if statement
I know there is a way for writing a Java if statement in short form.
15 Answers
15
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Why doesn't String switch statement support a null case?
I am just wondering why the Java 7 switch statement does not support a null case and instead throws NullPointerException ? See the commented line below (example taken from the Java Tutorials article on switch ):
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How do I convert a byte array to Base64 in Java?
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Java 8+
Encode or decode byte arrays:
byte[] encoded = Base64.getEncoder().encode("Hello".getBytes());
println(new String(encoded)); // Outputs "SGVsbG8="
byte[] decoded = Base64.getDecoder().decode(encoded);
println(new S...
How to override toString() properly in Java?
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@Amit The Java compiler uses StringBuilder implicitly. There's no problem unless you're using it in a loop.
– chrylis -cautiouslyoptimistic-
Jul 6 '17 at 23:37
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Is it good practice to use java.lang.String.intern()?
The Javadoc about String.intern() doesn't give much detail. (In a nutshell: It returns a canonical representation of the string, allowing interned strings to be compared using == )
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Interfaces with static fields in java for sharing 'constants'
I'm looking at some open source Java projects to get into Java and notice a lot of them have some sort of 'constants' interface.
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How do you return a JSON object from a Java Servlet
How do you return a JSON object form a Java servlet.
13 Answers
13
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How to insert a SQLite record with a datetime set to 'now' in Android application?
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You cannot use the datetime function using the Java wrapper "ContentValues". Either you can use :
SQLiteDatabase.execSQL so you can enter a raw SQL query.
mDb.execSQL("INSERT INTO "+DATABASE_TABLE+" VALUES (null, datetime()) ");
Or the java date time capabilities :
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How do I parse an ISO 8601-formatted date?
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Mark AmeryMark Amery
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Android: Difference between Parcelable and Serializable?
...lizable or Parcelable interface.
Serializable
Serializable is a standard Java interface. You can just implement Serializable interface and add override methods. The problem with this approach is that reflection is used and it is a slow process. This method creates a lot of temporary objects and ca...