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How can I “pretty print” a Duration in Java?
Does anyone know of a Java library that can pretty print a number in milliseconds in the same way that C# does?
11 Answers
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Do fragments really need an empty constructor?
...k: https://android.googlesource.com/platform/frameworks/base/+/master/core/java/android/app/Fragment.java
You will see the instantiate(..) method in the Fragment class calls the newInstance method:
public static Fragment instantiate(Context context, String fname, @Nullable Bundle args) {
try {...
Removing whitespace from strings in Java
...string is not modified as some of the answers sort of imply.
(Experienced Java developers might say "of course, you can't actually modify a String", but the target audience for this question may well not know this.)
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How to run Unix shell script from Java code?
It is quite simple to run a Unix command from Java.
17 Answers
17
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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 to convert Strings to and from UTF8 byte arrays in Java
In Java, I have a String and I want to encode it as a byte array (in UTF8, or some other encoding). Alternately, I have a byte array (in some known encoding) and I want to convert it into a Java String. How do I do these conversions?
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Java: is there a map function?
I need a map function. Is there something like this in Java already?
6 Answers
6
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How can I give the Intellij compiler more heap space?
...ss heap size.
Older versions:
Settings (Preferences on Mac) | Compiler | Java Compiler | Maximum heap size.
Compiler runs in a separate JVM by default so IDEA heap settings that you set in idea.vmoptions have no effect on the compiler.
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How can I truncate a double to only two decimal places in Java?
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If you want that for display purposes, use java.text.DecimalFormat:
new DecimalFormat("#.##").format(dblVar);
If you need it for calculations, use java.lang.Math:
Math.floor(value * 100) / 100;
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Whitespace Matching Regex - Java
The Java API for regular expressions states that \s will match whitespace. So the regex \\s\\s should match two spaces.
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