Questions tagged [defensive-copy]
31 questions
18
votes
7 answers
Defensive copy of Calendar
Been trying to find the best way to implement a method that makes a defensive copy of a Calendar object.
eg:
public void setDate(Calendar date) {
// What to do....
}
I am particularly concerned about interleaving of threads when checking for…
JJ Vester
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5
votes
2 answers
Inefficiency of defensive copy in Java
I'm a longtime C/C++ programmer who's learning Java. I've read about the problem of breaking encapsulation by having an accessor method that returns a reference to a private field. The standard Java solution seems to be defensive copying - calling…
Dave Beal
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4
votes
1 answer
If I have a c# readonly struct that has non readonly structs as members, will compiler create defensive copy with in parameter
so, if I have for example a struct PlayerData that has members of Vector3 structs defined in System.Numerics (not readonly structs)
public readonly struct PlayerData
{
public readonly Vector3 SpawnPoint;
public readonly Vector3…
JohnE
- 41
- 2
4
votes
2 answers
Objective-C defensive copying in accessor methods
Coming from a Java background, I'm having trouble figuring out ways to program defensively in Objective-C.
Assuming SomeClass is mutable and provides a copy method, this is a typical piece of code I'd write in Java:
public MyClass
{
private…
Dmitry
- 161
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3
votes
4 answers
Encapsulating a mutable object into a read-only object
I'm currently implementing iterative solvers, which work by successively improving the estimate the solution to a specific problem. As the solution is a rather large set of data, refinement is carried out in place.
I have implemented a simple…
Sebastien
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3
votes
2 answers
How do I make defensive copy of an object?
How do I make defensive copies of a Mutable Object which contains a mutable field in an Immutable Object?
class ImmutableObject {
private final MutableObject immutable_field;
ImmutableObject(MutableObject y) {
this.immutable_field = y;
…
unj2
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3
votes
3 answers
How to deal with various cases of defensive programming?
This is an example of defensive copy in Effective java. Assume that scenario's in my underlying questions need a defensive copy, and cannot do with a comment asking client to avoid mutating objects passed in.
public Period(Date start, Date end) {
…
JavaDeveloper
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3
votes
2 answers
Regarding an Immutable class defensive copying
I have a query regarding creating a Immutable class. Following are the points which I take in consideration:
Make the class final
Make all members final, set them explicitly, in a static block, or in the constructor
Make all members private
No…
Crazy4Java
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2
votes
1 answer
Create a Defensive Copy in the Constructor
The following is just example code to explain the problem I have trouble understanding:
Lets say I have the following Professor class, note the public getters and setters:
public class Professor
{
public string id {get; set; }
…
user5910494
2
votes
3 answers
Making a general copy of a Set in constructor
I did not find a direct answer to this specific question, so... Assume class:
class MyClass {
private final Set tags;
MyClass(Set initialTags) {
this.tags = ???(initialtags);
}
}
I just want a copy without…
hyde
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1
vote
5 answers
How do I append/prepend list in function without modifying source?
Given this source list:
source_list = [2, 3, 4]
and this function:
def function(list_in):
list_in.append(5)
list_in.insert(0, 1)
return list_in
As expected, I get:
>>> function(source_list)
[1, 2, 3, 4, 5]
But if I call the variable…
dandersen19
- 59
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1
vote
1 answer
SETQ or SETF With Defensive Copy
I am wondering about how one could do something as follows in Common Lisp. Suppose I have an object (entity) in memory that is unique at a certain time. What I would like to do is set some variable to be the state of that object, as snapshot at a…
MadPhysicist
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1
vote
1 answer
Correct Way of Creating a Defensive Copy of Custom Class
I've got the following class:
public class FolderAgent
{
public string directoryName {get; private set; }
public int numberofdirectories {get; private set; }
public int numberofFiles {get; private set;}
public…
user5910494
1
vote
2 answers
How do we make a java class immutable if it has a member variable of another user defined class?
Recently in an interview for Java Developer role, I was asked how do I make Class A immutable if it has a member variable, which is an object of Class B and in a situation where Class B is external to the project and cannot be edited by the…
Saurav Shekhar
- 21
- 3
1
vote
5 answers
LinkedList insert tied to inserted object
I have code that looks like this:
public class Polynomial {
List term = new LinkedList();
and it seems that whenever I do something like term.add(anotherTerm), with anotherTerm being... another Term object, it seems anotherTerm is…
wrongusername
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