Is usefull this method Collections.unmodifiableList?
By : Benign
Date : March 29 2020, 07:55 AM
I wish did fix the issue. It has two main advantages: While coding you can make a read-only collection class without making a subclass, you can use a generic read-only wrapper on every type of collection (re-usability) In the runtime you can create a read-only view of an existing collection without copying the whole collection to a read-only implementation (which is usually expensive) code :
class myComplicatedCollection<T> implements Collection<T> {
// Code goes here
// O no, I still have to deal with the read-only use-case.
// Instead of duplicating almost all of my code or using inheritance I'll use this handy-dandy wrapper
public Collection<T> readonlyVersion() {
return Collections.unmodifiableCollection(this);
}
}
class myClass {
private Collection<T> theData;
// Users need to access the data,
// but we don't want them modifying the private data of this class
public Collection<T> getTheData() {
return Collections.unmodifiableCollection(theData);
}
}
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operator '*' cannot be applied to operands of type 'double' and 'method' type
By : Yogesh Pawar
Date : March 29 2020, 07:55 AM
hop of those help? I am trying to multiply textboxes declared in form2 here in form3. on form2 i have , Your problem is here: code :
double.Parse(Form2.SetvalueforTextBox1).ToString()
label1.Text = (double.Parse(Form2.SetvalueforTextBox1) * double.Parse(Form2.SetvalueforTextBox1)).ToString();
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Why is it better to return unmodifiableList from a method where list is created?
By : vikash
Date : March 29 2020, 07:55 AM
wish help you to fix your issue When an object returns a mutable private field, it is exposed to unwanted/unknown alteration of its internal state by external agents, which violates encapsulation. The pattern to which you refer, called safe publishing, protects against this problem. It can be accomplished by returning either a deep copy, or the field (and any mutable sub-fields) in an immutable wrapper. code :
return Collections.unmodifiableList(xs);
return new ArrayList<>(xs);
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Operator '<' cannot be applied to operands of type 'method group' and 'Type'
By : user2827333
Date : March 29 2020, 07:55 AM
will be helpful for those in need You are using generic arguments incorrectly. You can register by type code :
containerBuilder.RegisterType(servicesList[i]);
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How to create a read-only list in java without using unmodifiablelist method from collections API?
By : Алексей Левченко
Date : March 29 2020, 07:55 AM
may help you . Just extend AbstractList. As the docs mention:
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