Questions tagged [cloneable]
163 questions
146
votes
3 answers
Why is Cloneable not deprecated?
It is commonly understood that Cloneable interface in Java is broken. There are many reasons for this, which I will not mention; others already did it. It is also the position of Java architects themselves.
My question is therefore: why has is not…
Kao
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125
votes
9 answers
How to properly override clone method?
I need to implement a deep clone in one of my objects which has no superclass.
What is the best way to handle the checked CloneNotSupportedException thrown by the superclass (which is Object)?
A coworker advised me to handle it the following…
Cuga
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117
votes
4 answers
Why should I implement ICloneable in c#?
Can you explain to me why I should inherit from ICloneable and implement the Clone() method?
If I want to do a deep copy, can't I just implement my method? Let's say MyClone()?
Why should I inherit from ICloneable? What are the advantages? Is it…
uinc
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107
votes
6 answers
How does Cloneable work in Java and how do I use it?
I would like to know the following:
Cloneable means we can have a clone or a copy of objects, by
implementing the Cloneable interface. What are the advantages and
disadvantages of doing that?
How does the recursive cloning happen if the object is…
daydreamer
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72
votes
3 answers
How to clone a struct storing a boxed trait object?
I wrote a program that has the trait Animal and the struct Dog implementing the trait. It also has a struct AnimalHouse storing an animal as a trait object Box.
trait Animal {
fn speak(&self);
}
struct Dog {
name: String,
}
impl…
Denis Kreshikhin
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59
votes
3 answers
instanceof - incompatible conditional operand types
The following compiles fine:
Object o = new Object();
System.out.println(o instanceof Cloneable);
But this doesn't:
String s = new String();
System.out.println(s instanceof Cloneable);
A compiler error is thrown.
What is the problem?
java_geek
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50
votes
8 answers
The method clone() from object is not visible?
Question:
package GoodQuestions;
public class MyClass {
MyClass() throws CloneNotSupportedException {
try {
throw new CloneNotSupportedException();
} catch(Exception e) {
e.printStackTrace();
}
…
sekhar
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33
votes
5 answers
Java: Rationale of the Cloneable interface
Why wasn't the .clone() method specified in the java.lang.Cloneable interface ?
Ande Turner
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27
votes
3 answers
What is the point in letting my class implement Cloneable?
I came across some class code that implements Clonable, the documentation states:
A class implements the Cloneable interface to indicate to the Object.clone() method that it is legal for that method to make a field-for-field copy of instances of…
Emil Adz
- 40,709
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21
votes
3 answers
How do I copy or clone a LinkedList-implemented Queue in Java?
I have a Queue q1, that is implemented as a LinkedList, and I want to define a Queue q2, that is a separate, but identical identical instance of Queue q1.
How do I do that since Queue does not implement Cloneable?
Razer
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19
votes
5 answers
Effective Java: Analysis of the clone() method
Consider the following from Effective Java Item 11 (Override clone judiciously) where Josh Bloch is explaining what is wrong with the clone() contract .
There are a number of problems with this contract. The provision that “no
constructors are…
Geek
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19
votes
4 answers
Confusion about cloneable interface and object.clone() in java
If I have:
class foo implements Cloneable
and then do:
bar = new foo();
bar.clone();
I get a shallow copy without needing to write any bar.clone() code like I normally would need to do when I implement an interface.
My understanding is that an…
ambertch
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15
votes
2 answers
Serializable, cloneable and memory use in Java
I am using an inner class that is a subclass of a HashMap. I have a String as the key and double[] as the values. I store about 200 doubles per double[]. I should be using around 700 MB to store the keys, the pointers and the doubles. However,…
fiacobelli
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15
votes
6 answers
Why Object clone() method available only to classes that implement Cloneable interface?
I know that clone() is a protected method, but "protected" means that it is accessible for all subclasses of particular class.
Any Java class is a subclass of Object, so what is the reason for the protected method here?
And why can we call clone()…
Don_Quijote
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13
votes
4 answers
What is this field-by-field copy done by Object.clone()?
In Effective Java, the author states that:
If a class implements Cloneable,
Object's clone method returns a
field-by-field copy of the object;
otherwise it throws
CloneNotSupportedException.
What I'd like to know is what he means with…
devoured elysium
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