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Filtering for empty or NULL names in a queryset
...exclude(alias__isnull=True)
If you need to exclude null values and empty strings, the preferred way to do so is to chain together the conditions like so:
Name.objects.exclude(alias__isnull=True).exclude(alias__exact='')
Chaining these methods together basically checks each condition independent...
Espresso: Thread.sleep( );
...{
return isRoot();
}
@Override
public String getDescription() {
return "wait for a specific view with id <" + viewId + "> during " + millis + " millis.";
}
@Override
public void perform(final UiController uiController, f...
“new” keyword in Scala
...nelyGuy.type = LonelyGuy$@3449a8
scala> LonelyGuy.mood
res4: java.lang.String = sad
With a case classes (actually, underneath there are class + object = companion pattern, e.g. having class and object with the same name):
scala> case class Foo(bar: String)
defined class Foo
scala> Fo...
How do I tell if a regular file does not exist in Bash?
... you are free to edit my post and add it to the list. I guess you mean: -n String - Check if the length of the string isn't zero. Or do you mean file1 -nt file2 - Check if file1 is newer then file 2 (you can also use -ot for older then)
– BlueCacti
May 5 '14 at...
How to check if a folder exists
...
Generate a file from the string of your folder directory
String path="Folder directory";
File file = new File(path);
and use method exist.
If you want to generate the folder you sould use mkdir()
if (!file.exists()) {
System.out....
How do I create a file and write to it in Java?
...can use the Files class to write to files:
Creating a text file:
List<String> lines = Arrays.asList("The first line", "The second line");
Path file = Paths.get("the-file-name.txt");
Files.write(file, lines, StandardCharsets.UTF_8);
//Files.write(file, lines, StandardCharsets.UTF_8, StandardO...
How to annotate MYSQL autoincrement field with JPA annotations
...
Please make sure that id datatype is Long instead of String, if that
will be string then @GeneratedValue annotation will not work and the
sql generating for
@Id @GeneratedValue(strategy=GenerationType.IDENTITY)
private String id;
create table VMS_AUDIT_RECORDS (id **varc...
Javascript what is property in hasOwnProperty?
...Property("name")); //true
console.log(Object.prototype.hasOwnProperty("toString");) //true because in above snapshot you can see, that there is a function toString in meta-information
I hope it's clear !
share
...
Cache busting via params
...
The param ?v=1.123 indicates a query string, and the browser will therefore think it is a new path from, say, ?v=1.0. Thus causing it to load from file, not from cache. As you want.
And, the browser will assume that the source will stay the same next time you ...
Rails ActionMailer - format sender and recipient name/email address
... email, you can end up with an invalid From header by simply concatenating strings. Here is a safe way:
require 'mail'
address = Mail::Address.new email # ex: "john@example.com"
address.display_name = name.dup # ex: "John Doe"
# Set the From or Reply-To header to the following:
address.format # r...