Return Set with random unique Integer numbers between min and max range
0
I need set of random unique Integer numbers for my unit test. I implemented this method, however I'm not sure if this is best way to implement this.
private Set<Integer> getRandomUniqueNumberSet(Integer min, Integer max)
{
Set<Integer> added = new LinkedHashSet<Integer>();
for(int i = min; i <= max; i++)
{
Integer index = ThreadLocalRandom.current().nextInt(min, max + 1);
Boolean loop = false;
if(!added.add(index)) loop = true;
while(loop)
{
index = ThreadLocalRandom.current().nextInt(min, max + 1);
if(added.add(index)) loop = false;
}
}
return added;
}
Example:
for(Integer index : getRandomUniqueNumberSet(2, 15))
{
System.out.println("Index: " + index);
}
Results:
Index: 8
Index: 5
Index: 15
Index: 9
Index: 4
Index: 3
Index: 7
Index: 2
Index: 11
Index: 14
Index: 6
Index: 10
Index: 13
Index: 12
java
asked 56 mins ago
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101
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0
I need set of random unique Integer numbers for my unit test. I implemented this method, however I'm not sure if this is best way to implement this.
private Set<Integer> getRandomUniqueNumberSet(Integer min, Integer max)
{
Set<Integer> added = new LinkedHashSet<Integer>();
for(int i = min; i <= max; i++)
{
Integer index = ThreadLocalRandom.current().nextInt(min, max + 1);
Boolean loop = false;
if(!added.add(index)) loop = true;
while(loop)
{
index = ThreadLocalRandom.current().nextInt(min, max + 1);
if(added.add(index)) loop = false;
}
}
return added;
}
Example:
for(Integer index : getRandomUniqueNumberSet(2, 15))
{
System.out.println("Index: " + index);
}
Results:
Index: 8
Index: 5
Index: 15
Index: 9
Index: 4
Index: 3
Index: 7
Index: 2
Index: 11
Index: 14
Index: 6
Index: 10
Index: 13
Index: 12
java
asked 56 mins ago
newbie
101
New contributor
newbie is a new contributor to this site. Take care in asking for clarification, commenting, and answering.
Check out our Code of Conduct.
3
Note that your code is not doing much more than shuffling a collection of unique values. Have a look at this question which does something similar (in C#): codereview.stackexchange.com/q/61338/31503
– rolfl♦
43 mins ago
1
Welcome to Code Review! I support the suggestion of @rolfl: Just create a hard coded list (usingArrays.asList()) an useCollections.shuffle()to randomize it. Keep in mind that Unittest should have as less logic as possible.
– Timothy Truckle
32 mins ago
add a comment |
0
0
0
I need set of random unique Integer numbers for my unit test. I implemented this method, however I'm not sure if this is best way to implement this.
private Set<Integer> getRandomUniqueNumberSet(Integer min, Integer max)
{
Set<Integer> added = new LinkedHashSet<Integer>();
for(int i = min; i <= max; i++)
{
Integer index = ThreadLocalRandom.current().nextInt(min, max + 1);
Boolean loop = false;
if(!added.add(index)) loop = true;
while(loop)
{
index = ThreadLocalRandom.current().nextInt(min, max + 1);
if(added.add(index)) loop = false;
}
}
return added;
}
Example:
for(Integer index : getRandomUniqueNumberSet(2, 15))
{
System.out.println("Index: " + index);
}
Results:
Index: 8
Index: 5
Index: 15
Index: 9
Index: 4
Index: 3
Index: 7
Index: 2
Index: 11
Index: 14
Index: 6
Index: 10
Index: 13
Index: 12
java
asked 56 mins ago
newbie
101
New contributor
newbie is a new contributor to this site. Take care in asking for clarification, commenting, and answering.
Check out our Code of Conduct.
I need set of random unique Integer numbers for my unit test. I implemented this method, however I'm not sure if this is best way to implement this.
private Set<Integer> getRandomUniqueNumberSet(Integer min, Integer max)
{
Set<Integer> added = new LinkedHashSet<Integer>();
for(int i = min; i <= max; i++)
{
Integer index = ThreadLocalRandom.current().nextInt(min, max + 1);
Boolean loop = false;
if(!added.add(index)) loop = true;
while(loop)
{
index = ThreadLocalRandom.current().nextInt(min, max + 1);
if(added.add(index)) loop = false;
}
}
return added;
}
Example:
for(Integer index : getRandomUniqueNumberSet(2, 15))
{
System.out.println("Index: " + index);
}
Results:
Index: 8
Index: 5
Index: 15
Index: 9
Index: 4
Index: 3
Index: 7
Index: 2
Index: 11
Index: 14
Index: 6
Index: 10
Index: 13
Index: 12
java
java
asked 56 mins ago
newbie
101
New contributor
newbie is a new contributor to this site. Take care in asking for clarification, commenting, and answering.
Check out our Code of Conduct.
asked 56 mins ago
newbie
101
New contributor
newbie is a new contributor to this site. Take care in asking for clarification, commenting, and answering.
Check out our Code of Conduct.
asked 56 mins ago
newbie
101
New contributor
newbie is a new contributor to this site. Take care in asking for clarification, commenting, and answering.
Check out our Code of Conduct.
asked 56 mins ago
newbie
101
asked 56 mins ago
newbie
101
101
New contributor
newbie is a new contributor to this site. Take care in asking for clarification, commenting, and answering.
Check out our Code of Conduct.
New contributor
newbie is a new contributor to this site. Take care in asking for clarification, commenting, and answering.
Check out our Code of Conduct.
newbie is a new contributor to this site. Take care in asking for clarification, commenting, and answering.
Check out our Code of Conduct.
3
Note that your code is not doing much more than shuffling a collection of unique values. Have a look at this question which does something similar (in C#): codereview.stackexchange.com/q/61338/31503
– rolfl♦
43 mins ago
1
Welcome to Code Review! I support the suggestion of @rolfl: Just create a hard coded list (usingArrays.asList()) an useCollections.shuffle()to randomize it. Keep in mind that Unittest should have as less logic as possible.
– Timothy Truckle
32 mins ago
add a comment |
3
Note that your code is not doing much more than shuffling a collection of unique values. Have a look at this question which does something similar (in C#): codereview.stackexchange.com/q/61338/31503
– rolfl♦
43 mins ago
1
Welcome to Code Review! I support the suggestion of @rolfl: Just create a hard coded list (usingArrays.asList()) an useCollections.shuffle()to randomize it. Keep in mind that Unittest should have as less logic as possible.
– Timothy Truckle
32 mins ago
3
3
Note that your code is not doing much more than shuffling a collection of unique values. Have a look at this question which does something similar (in C#): codereview.stackexchange.com/q/61338/31503
– rolfl♦
43 mins ago
Note that your code is not doing much more than shuffling a collection of unique values. Have a look at this question which does something similar (in C#): codereview.stackexchange.com/q/61338/31503
– rolfl♦
43 mins ago
1
1
Welcome to Code Review! I support the suggestion of @rolfl: Just create a hard coded list (using
Arrays.asList()) an use Collections.shuffle() to randomize it. Keep in mind that Unittest should have as less logic as possible.– Timothy Truckle
32 mins ago
Welcome to Code Review! I support the suggestion of @rolfl: Just create a hard coded list (using
Arrays.asList()) an use Collections.shuffle() to randomize it. Keep in mind that Unittest should have as less logic as possible.– Timothy Truckle
32 mins ago
add a comment |
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3
Note that your code is not doing much more than shuffling a collection of unique values. Have a look at this question which does something similar (in C#): codereview.stackexchange.com/q/61338/31503
– rolfl♦
43 mins ago
1
Welcome to Code Review! I support the suggestion of @rolfl: Just create a hard coded list (using
Arrays.asList()) an useCollections.shuffle()to randomize it. Keep in mind that Unittest should have as less logic as possible.– Timothy Truckle
32 mins ago