rspec/rules/S5413/java/rule.adoc

== Why is this an issue?

When ``++List.remove()++`` is called it will shrink the list. If this is done inside the ascending loop iterating through all elements it will skip the element after the removed index.


=== Noncompliant code example

[source,java]
----
void removeFrom(List<String> list) {
  // expected: iterate over all the elements of the list
  for (int i = 0; i < list.size(); i++) {
    if (list.get(i).isEmpty()) {
      // actual: remaining elements are shifted, so the one immediately following will be skipped
      list.remove(i); // Noncompliant
    }
  }
}
----


=== Compliant solution

You can either adjust the loop index to account for the change in the size of the list

[source,java]
----
static void removeFrom(List<String> list) {
    // expected: iterate over all the elements of the list
    for (int i = 0; i < list.size(); i++) {
      if (list.get(i).isEmpty()) {
        // actual: remaining elements are shifted, so the one immediately following will be skipped
        list.remove(i);
        i--;
      }
    }
  }
----
Or preferably it's probably better to rely on Java 8's ``++removeIf++`` method

[source,java]
----
 static void removeFrom(List<String> list) {
    list.removeIf(String::isEmpty);
  }
----
 


=== Exceptions

The descending loop doesn't have this issue, because the index will be correct when we loop in descending order

----
void removeFrom(List<String> list) {
  for (int i = list.size() - 1; i >= 0; i--) {
    if (list.get(i).isEmpty()) {
      list.remove(i);
    }
  }
}
----
 

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== Implementation Specification
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