Examples of errors detected by the V6013 diagnostic

V6013. Comparison of arrays, strings, collections by reference. Possibly an equality comparison was intended.

Elasticsearch

V6013 Numbers 'displaySize' and 'that.displaySize' are compared by reference. Possibly an equality comparison was intended. ColumnInfo.java(122)

....
private final String table;
private final String name;
private final String esType;
private final Integer displaySize;
....
@Override
public boolean equals(Object o) {
    if (this == o) {
        return true;
    }
    if (o == null || getClass() != o.getClass()) {
        return false;
    }
    ColumnInfo that = (ColumnInfo) o;
    return displaySize == that.displaySize &&    // <=
           Objects.equals(table, that.table) &&
           Objects.equals(name, that.name) &&
           Objects.equals(esType, that.esType);
}