apache/druid · error · IAE

Size[%d] > expansion.length[%d] or < 0

Error message

Size[%d] > expansion.length[%d] or < 0

What it means

ArrayBasedIndexedInts.setSize(int) validates that the requested active size is non-negative and does not exceed the capacity of the internal expansion array, throwing IAE otherwise. It is used to reuse the object over a fixed backing array.

Source

Thrown at processing/src/main/java/org/apache/druid/segment/data/ArrayBasedIndexedInts.java:57

  }

  public ArrayBasedIndexedInts(int[] expansion)
  {
    this.expansion = expansion;
    this.size = expansion.length;
  }

  public void ensureSize(int size)
  {
    if (expansion.length < size) {
      expansion = new int[size];
    }
  }

  public void setSize(int size)
  {
    if (size < 0 || size > expansion.length) {
      throw new IAE("Size[%d] > expansion.length[%d] or < 0", size, expansion.length);
    }
    this.size = size;
  }

  /**
   * Sets the values from the given array. The given values array is not reused and not prone to be mutated later.
   * Instead, the values from this array are copied into an array which is internal to ArrayBasedIndexedInts.
   */
  public void setValues(int[] values, int size)
  {
    if (size < 0 || size > values.length) {
      throw new IAE("Size[%d] should be between 0 and %d", size, values.length);
    }
    ensureSize(size);
    System.arraycopy(values, 0, expansion, 0, size);
    this.size = size;
  }

View on GitHub (pinned to 9b90983fd2)

Solutions

1. Ensure the backing array passed to the constructor is at least as large as the maximum size set
2. Call ensureSize(size) before setSize to grow the internal array
3. Validate size >= 0 before calling

Example fix

// before
indexedInts.setSize(values.length);
// after
indexedInts.ensureSize(values.length);
indexedInts.setSize(values.length);

if (size >= 0 && size <= expansion.length) { indexed.setSize(size); }

boolean canSetSize(ArrayBasedIndexedInts v, int size) { return size >= 0 && size <= v.size() || size <= v.inspectArrayCapacity(); } // use documented capacity

try { indexed.setSize(size); } catch (IAE e) { indexed.ensureSize(size); indexed.setSize(size); }

When it happens

Trigger: Calling setSize with a negative value or a value larger than the array passed at construction (expansion.length), e.g. from initColumnValues with a bigger row than the allocated array.

Common situations: Reusing a pooled ArrayBasedIndexedInts across rows/columns with mismatched capacities; off-by-one or wrong initial allocation size.

Understand the failure class

Background: "value must be between 0 and 1" / "out of range" / "must not be negative" errors: fixing range-validation failures across open-source libraries — this error's family across 42 libraries.

Related errors

• Size[%d] should be between 0 and %d
• Index[%d] >= size[%d]
• Column is not multi-valued
• Not a numeric value type:
• index[%d] >= size[%d] or < 0

AI-assisted analysis of apache/druid@9b90983fd2 (2026-09-07). Data as JSON: /api/errors/a0e9837d10c8aac1. Report an issue: GitHub.