checker/tests/interning/Arrays.java

import java.util.ArrayList;
import java.util.List;
import org.checkerframework.checker.interning.qual.Interned;
import org.checkerframework.checker.interning.qual.PolyInterned;

public class Arrays {

  public static Integer[] arrayclone_simple(Integer[] a_old) {
    int len = a_old.length;
    Integer[] a_new = new Integer[len];
    for (int i = 0; i < len; i++) {
      a_new[i] = Integer.valueOf(a_old[i]); // valid
    }
    return a_new;
  }

  public static void test(@Interned Integer i, @Interned String s) {
    String @Interned [] iarray1 = new String @Interned [2];
    String @Interned [] iarray2 = new String @Interned [] {"foo", "bar"};
    // :: error: (assignment)
    s = iarray1[1]; // error

    String[] sa = new String[22];
    // :: error: (assignment)
    iarray1 = sa; // error
    sa = iarray1; // OK

    @Interned String[] istrings1 = new @Interned String[2];
    @Interned String[] istrings2 = new @Interned String[] {"foo", "bar"};
    s = istrings1[1]; // OK

    @Interned String @Interned [][] multi1 = new @Interned String @Interned [2][3];
    @Interned String @Interned [][] multi2 = new @Interned String @Interned [2][];
  }

  public final @Interned class InternedClass {}

  private static InternedClass[] returnToArray() {
    List<InternedClass> li = new ArrayList<>();
    return li.toArray(new InternedClass[li.size()]);
  }

  private static void sortIt() {
    java.util.Arrays.sort(new InternedClass[22]);
  }

  private @Interned String[] elts_String;

  public @Interned String min_elt() {
    return elts_String[0];
  }

  private double @Interned [] @Interned [] elts_da;

  public void add_mod_elem(double @Interned [] v, int count) {
    elts_da[0] = v;
  }

  public static @PolyInterned Object[] subarray(
      @PolyInterned Object[] a, int startindex, int length) {
    @PolyInterned Object[] result = new @PolyInterned Object[length];
    System.arraycopy(a, startindex, result, 0, length);
    return result;
  }

  public static void trim(int len) {
    @Interned Object @Interned [] vals = null;
    @Interned Object[] new_vals = subarray(vals, 0, len);
  }

  public static @Interned Object @Interned [] internSubsequence(
      @Interned Object @Interned [] seq, int start, int end) {
    @Interned Object[] subseq_uninterned = subarray(seq, start, end - start);
    return null;
  }
}