luni/src/test/java/libcore/java/util/ArraysTest.java - platform/libcore - Git at Google

 /*
  * Copyright (C) 2016 The Android Open Source Project
  *
  * Licensed under the Apache License, Version 2.0 (the "License");
  * you may not use this file except in compliance with the License.
  * You may obtain a copy of the License at
  *
  *      http://www.apache.org/licenses/LICENSE-2.0
  *
  * Unless required by applicable law or agreed to in writing, software
  * distributed under the License is distributed on an "AS IS" BASIS,
  * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
  * See the License for the specific language governing permissions and
  * limitations under the License
  */

 package libcore.java.util;

 import java.util.Arrays;
 import java.util.Random;

 public class ArraysTest extends junit.framework.TestCase {

     /**
      * java.util.Arrays#setAll(int[], java.util.function.IntUnaryOperator)
      */
     public void test_setAll$I() {
         int[] list = new int[3];
         list[0] = 0;
         list[1] = 1;
         list[2] = 2;

         Arrays.setAll(list, x -> x + 1);
         assertEquals(1, list[0]);
         assertEquals(2, list[1]);
         assertEquals(3, list[2]);

         try {
             Arrays.setAll(list, null);
             fail();
         } catch (NullPointerException expected) {
         }

         try {
             Arrays.setAll((int[]) null, (x -> x + 1));
             fail();
         } catch (NullPointerException expected) {
         }
     }

     /**
      * java.util.Arrays#parallelSetAll(int[], java.util.function.IntUnaryOperator)
      */
     public void test_parallelSetAll$I() {
         int[] list = new int[3];
         list[0] = 0;
         list[1] = 1;
         list[2] = 2;

         Arrays.parallelSetAll(list, x -> x + 1);
         assertEquals(1, list[0]);
         assertEquals(2, list[1]);
         assertEquals(3, list[2]);

         try {
             Arrays.parallelSetAll(list, null);
             fail();
         } catch (NullPointerException expected) {
         }

         try {
             Arrays.parallelSetAll((int[]) null, (x -> x + 1));
             fail();
         } catch (NullPointerException expected) {
         }
     }

     /**
      * java.util.Arrays#setAll(long[], java.util.function.IntToLongFunction)
      */
     public void test_setAll$L() {
         long[] list = new long[3];
         list[0] = 0;
         list[1] = 1;
         list[2] = 2;

         Arrays.setAll(list, x -> x + 1);
         assertEquals(1, list[0]);
         assertEquals(2, list[1]);
         assertEquals(3, list[2]);

         try {
             Arrays.setAll(list, null);
             fail();
         } catch (NullPointerException expected) {
         }

         try {
             Arrays.setAll((long[]) null, (x -> x + 1));
             fail();
         } catch (NullPointerException expected) {
         }
     }

     /**
      * java.util.Arrays#parallelSetAll(long[], java.util.function.IntToLongFunction)
      */
     public void test_parallelSetAll$L() {
         long[] list = new long[3];
         list[0] = 0;
         list[1] = 1;
         list[2] = 2;

         Arrays.parallelSetAll(list, x -> x + 1);
         assertEquals(1, list[0]);
         assertEquals(2, list[1]);
         assertEquals(3, list[2]);

         try {
             Arrays.parallelSetAll(list, null);
             fail();
         } catch (NullPointerException expected) {
         }

         try {
             Arrays.parallelSetAll((long[]) null, (x -> x + 1));
             fail();
         } catch (NullPointerException expected) {
         }
     }

     /**
      * java.util.Arrays#setAll(double[], java.util.function.IntToDoubleFunction)
      */
     public void test_setAll$D() {
         double[] list = new double[3];
         list[0] = 0.0d;
         list[1] = 1.0d;
         list[2] = 2.0d;

         Arrays.setAll(list, x -> x + 0.5);
         assertEquals(0.5d, list[0]);
         assertEquals(1.5d, list[1]);
         assertEquals(2.5d, list[2]);

         try {
             Arrays.setAll(list, null);
             fail();
         } catch (NullPointerException expected) {
         }

         try {
             Arrays.setAll((double[]) null, x -> x + 0.5);
             fail();
         } catch (NullPointerException expected) {
         }
     }

     /**
      * java.util.Arrays#parallelSetAll(double[], java.util.function.IntToDoubleFunction)
      */
     public void test_parallelSetAll$D() {
         double[] list = new double[3];
         list[0] = 0.0d;
         list[1] = 1.0d;
         list[2] = 2.0d;

         Arrays.parallelSetAll(list, x -> x + 0.5);
         assertEquals(0.5d, list[0]);
         assertEquals(1.5d, list[1]);
         assertEquals(2.5d, list[2]);

         try {
             Arrays.parallelSetAll(list, null);
             fail();
         } catch (NullPointerException expected) {
         }

         try {
             Arrays.parallelSetAll((double[]) null, x -> x + 0.5);
             fail();
         } catch (NullPointerException expected) {
         }
     }

     /**
      * java.util.Array#setAll(T[], java.util.function.IntFunction<\? extends T>)
      */
     public void test_setAll$T() {
         String[] strings = new String[3];
         strings[0] = "a";
         strings[0] = "b";
         strings[0] = "c";

         Arrays.setAll(strings, x -> "a" + x);
         assertEquals("a0", strings[0]);
         assertEquals("a1", strings[1]);
         assertEquals("a2", strings[2]);

         try {
             Arrays.setAll(strings, null);
             fail();
         } catch (NullPointerException expected) {
         }

         try {
             Arrays.setAll((String[]) null, x -> "a" + x);
             fail();
         } catch (NullPointerException expected) {
         }
     }

     /**
      * java.util.Array#parallelSetAll(T[], java.util.function.IntFunction<\? extends T>)
      */
     public void test_parallelSetAll$T() {
         String[] strings = new String[3];
         strings[0] = "a";
         strings[0] = "b";
         strings[0] = "c";

         Arrays.parallelSetAll(strings, x -> "a" + x);
         assertEquals("a0", strings[0]);
         assertEquals("a1", strings[1]);
         assertEquals("a2", strings[2]);

         try {
             Arrays.parallelSetAll(strings, null);
             fail();
         } catch (NullPointerException expected) {
         }

         try {
             Arrays.parallelSetAll((String[]) null, x -> "a" + x);
             fail();
         } catch (NullPointerException expected) {
         }
     }

     /**
      * java.util.Array#parallelPrefix(int[], java.util.function.IntBinaryOperator)
      */
     public void test_parallelPrefix$I() {
         // Get an arbitrary array of ints.
         Random rand = new Random(0);
         int[] list = new int[1000];
         for(int i = 0; i < list.length; ++i) {
             list[i] = rand.nextInt() % 1000; // Prevent overflow
         }

         int[] seqResult = list.clone();

         // Sequential solution
         for(int i = 0; i < seqResult.length - 1; ++i) {
             seqResult[i + 1] += seqResult[i];
         }

         Arrays.parallelPrefix(list, (x, y) -> x + y);
         assertTrue(Arrays.equals(seqResult, list));

         try {
             Arrays.parallelPrefix(list, null);
             fail();
         } catch (NullPointerException expected) {
         }

         try {
             Arrays.parallelPrefix((int[]) null, (x, y) -> x + y);
             fail();
         } catch (NullPointerException expected) {
         }
     }

     /**
      * java.util.Array#parallelPrefix(int[], int, int, java.util.function.IntBinaryOperator)
      */
     public void test_parallelPrefix$III() {
         // Get an arbitrary array of ints.
         Random rand = new Random(0);
         int[] list = new int[1000];
         for(int i = 0; i < list.length; ++i) {
             list[i] = rand.nextInt() % 1000; // Prevent overflow
         }

         int begin = 100, end = 500;
         int[] seqResult = list.clone();

         // Sequential solution
         for(int i = begin; i < end - 1; ++i) {
             seqResult[i + 1] += seqResult[i];
         }

         Arrays.parallelPrefix(list, begin, end, (x, y) -> x + y);
         assertTrue(Arrays.equals(seqResult, list));

         try {
             Arrays.parallelPrefix(list, begin, end, null);
             fail();
         } catch (NullPointerException expected) {
         }

         try {
             Arrays.parallelPrefix((int[]) null, begin, end, (x, y) -> x + y);
             fail();
         } catch (NullPointerException expected) {
         }

         try {
             Arrays.parallelPrefix(list, end, begin, (x, y) -> x + y);
             fail();
         } catch (IllegalArgumentException expected) {
         }
     }

     /**
      * java.util.Array#parallelPrefix(long[], java.util.function.LongBinaryOperator)
      */
     public void test_parallelPrefix$L() {
         // Get an arbitrary array of ints.
         Random rand = new Random(0);
         long[] list = new long[1000];
         for(int i = 0; i < list.length; ++i) {
             list[i] = rand.nextLong() % 1000000; // Prevent overflow
         }

         long[] seqResult = list.clone();

         // Sequential solution
         for(int i = 0; i < seqResult.length - 1; ++i) {
             seqResult[i + 1] += seqResult[i];
         }

         Arrays.parallelPrefix(list, (x, y) -> x + y);
         assertTrue(Arrays.equals(seqResult, list));

         try {
             Arrays.parallelPrefix(list, null);
             fail();
         } catch (NullPointerException expected) {
         }

         try {
             Arrays.parallelPrefix((long[]) null, (x, y) -> x + y);
             fail();
         } catch (NullPointerException expected) {
         }
     }

     /**
      * java.util.Array#parallelPrefix(long[], int, int, java.util.function.LongBinaryOperator)
      */
     public void test_parallelPrefix$LII() {
         // Get an arbitrary array of ints.
         Random rand = new Random(0);
         long[] list = new long[1000];
         for(int i = 0; i < list.length; ++i) {
             list[i] = rand.nextLong() % 1000000; // Prevent overflow
         }

         int begin = 100, end = 500;
         long[] seqResult = list.clone();

         // Sequential solution
         for(int i = begin; i < end - 1; ++i) {
             seqResult[i + 1] += seqResult[i];
         }

         Arrays.parallelPrefix(list, begin, end, (x, y) -> x + y);
         assertTrue(Arrays.equals(seqResult, list));

         try {
             Arrays.parallelPrefix(list, begin, end, null);
             fail();
         } catch (NullPointerException expected) {
         }

         try {
             Arrays.parallelPrefix((long[]) null, begin, end, (x, y) -> x + y);
             fail();
         } catch (NullPointerException expected) {
         }

         try {
             Arrays.parallelPrefix(list, end, begin, (x, y) -> x + y);
             fail();
         } catch (IllegalArgumentException expected) {
         }
     }

     /**
      * java.util.Array#parallelPrefix(double[], java.util.function.DoubleBinaryOperator)
      */
     public void test_parallelPrefix$D() {
         // Get an arbitrary array of ints.
         Random rand = new Random(0);
         double[] list = new double[1000];
         for(int i = 0; i < list.length; ++i) {
             list[i] = rand.nextDouble() * 1000;
         }

         double[] seqResult = list.clone();

         // Sequential solution
         for(int i = 0; i < seqResult.length - 1; ++i) {
             seqResult[i + 1] += seqResult[i];
         }

         Arrays.parallelPrefix(list, (x, y) -> x + y);

         // Parallel double arithmetic contains error, reduce to integer for comparison.
         int[] listInInt = Arrays.stream(list).mapToInt(x -> (int) x).toArray();
         int[] seqResultInInt = Arrays.stream(seqResult).mapToInt(x -> (int) x).toArray();
         assertTrue(Arrays.equals(seqResultInInt, listInInt));

         try {
             Arrays.parallelPrefix(list, null);
             fail();
         } catch (NullPointerException expected) {
         }

         try {
             Arrays.parallelPrefix((double[]) null, (x, y) -> x + y);
             fail();
         } catch (NullPointerException expected) {
         }
     }

     /**
      * java.util.Array#parallelPrefix(double[], int, int, java.util.function.DoubleBinaryOperator)
      */
     public void test_parallelPrefix$DII() {
         // Get an arbitrary array of ints.
         Random rand = new Random(0);
         double[] list = new double[1000];
         for(int i = 0; i < list.length; ++i) {
             list[i] = rand.nextDouble() * 1000;
         }

         int begin = 100, end = 500;
         double[] seqResult = list.clone();

         // Sequential solution
         for(int i = begin; i < end - 1; ++i) {
             seqResult[i + 1] += seqResult[i];
         }

         Arrays.parallelPrefix(list, begin, end, (x, y) -> x + y);

         // Parallel double arithmetic contains error, reduce to integer for comparison.
         int[] listInInt = Arrays.stream(list).mapToInt(x -> (int) x).toArray();
         int[] seqResultInInt = Arrays.stream(seqResult).mapToInt(x -> (int) x).toArray();
         assertTrue(Arrays.equals(seqResultInInt, listInInt));

         try {
             Arrays.parallelPrefix(list, begin, end, null);
             fail();
         } catch (NullPointerException expected) {
         }

         try {
             Arrays.parallelPrefix((double[]) null, begin, end, (x, y) -> x + y);
             fail();
         } catch (NullPointerException expected) {
         }

         try {
             Arrays.parallelPrefix(list, end, begin, (x, y) -> x + y);
             fail();
         } catch (IllegalArgumentException expected) {
         }
     }

     /**
      * java.util.Array#parallelPrefix(T[], java.util.function.BinaryOperator<T>)
      */
     public void test_parallelPrefix$T() {
         String[] strings = new String[3];
         strings[0] = "a";
         strings[1] = "b";
         strings[2] = "c";

         Arrays.parallelPrefix(strings, (x, y) -> x + y);
         assertEquals("a", strings[0]);
         assertEquals("ab", strings[1]);
         assertEquals("abc", strings[2]);

         try {
             Arrays.parallelPrefix(strings, null);
             fail();
         } catch (NullPointerException expected) {
         }

         try {
             Arrays.parallelPrefix((String[]) null, (x, y) -> x + y);
             fail();
         } catch (NullPointerException expected) {
         }
     }

     /**
      * java.util.Array#parallelPrefix(T[], int, int, java.util.function.BinaryOperator<T>)
      */
     public void test_parallelPrefix$TII() {
         String[] strings = new String[5];
         strings[0] = "a";
         strings[1] = "b";
         strings[2] = "c";
         strings[3] = "d";
         strings[4] = "e";
         int begin = 1, end = 4;

         Arrays.parallelPrefix(strings, begin, end, (x, y) -> x + y);
         assertEquals("a", strings[0]);
         assertEquals("b", strings[1]);
         assertEquals("bc", strings[2]);
         assertEquals("bcd", strings[3]);
         assertEquals("e", strings[4]);

         try {
             Arrays.parallelPrefix(strings, begin, end, null);
             fail();
         } catch (NullPointerException expected) {
         }

         try {
             Arrays.parallelPrefix((String[]) null, begin, end, (x, y) -> x + y);
             fail();
         } catch (NullPointerException expected) {
         }

         try {
             Arrays.parallelPrefix(strings, end, begin, (x, y) -> x + y);
             fail();
         } catch (IllegalArgumentException expected) {
         }
     }
 }
	/*
	* Copyright (C) 2016 The Android Open Source Project
	*
	* Licensed under the Apache License, Version 2.0 (the "License");
	* you may not use this file except in compliance with the License.
	* You may obtain a copy of the License at
	*
	* http://www.apache.org/licenses/LICENSE-2.0
	*
	* Unless required by applicable law or agreed to in writing, software
	* distributed under the License is distributed on an "AS IS" BASIS,
	* WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
	* See the License for the specific language governing permissions and
	* limitations under the License
	*/

	package libcore.java.util;

	import java.util.Arrays;
	import java.util.Random;

	public class ArraysTest extends junit.framework.TestCase {

	/**
	* java.util.Arrays#setAll(int[], java.util.function.IntUnaryOperator)
	*/
	public void test_setAll$I() {
	int[] list = new int[3];
	list[0] = 0;
	list[1] = 1;
	list[2] = 2;

	Arrays.setAll(list, x -> x + 1);
	assertEquals(1, list[0]);
	assertEquals(2, list[1]);
	assertEquals(3, list[2]);

	try {
	Arrays.setAll(list, null);
	fail();
	} catch (NullPointerException expected) {
	}

	try {
	Arrays.setAll((int[]) null, (x -> x + 1));
	fail();
	} catch (NullPointerException expected) {
	}
	}

	/**
	* java.util.Arrays#parallelSetAll(int[], java.util.function.IntUnaryOperator)
	*/
	public void test_parallelSetAll$I() {
	int[] list = new int[3];
	list[0] = 0;
	list[1] = 1;
	list[2] = 2;

	Arrays.parallelSetAll(list, x -> x + 1);
	assertEquals(1, list[0]);
	assertEquals(2, list[1]);
	assertEquals(3, list[2]);

	try {
	Arrays.parallelSetAll(list, null);
	fail();
	} catch (NullPointerException expected) {
	}

	try {
	Arrays.parallelSetAll((int[]) null, (x -> x + 1));
	fail();
	} catch (NullPointerException expected) {
	}
	}

	/**
	* java.util.Arrays#setAll(long[], java.util.function.IntToLongFunction)
	*/
	public void test_setAll$L() {
	long[] list = new long[3];
	list[0] = 0;
	list[1] = 1;
	list[2] = 2;

	Arrays.setAll(list, x -> x + 1);
	assertEquals(1, list[0]);
	assertEquals(2, list[1]);
	assertEquals(3, list[2]);

	try {
	Arrays.setAll(list, null);
	fail();
	} catch (NullPointerException expected) {
	}

	try {
	Arrays.setAll((long[]) null, (x -> x + 1));
	fail();
	} catch (NullPointerException expected) {
	}
	}

	/**
	* java.util.Arrays#parallelSetAll(long[], java.util.function.IntToLongFunction)
	*/
	public void test_parallelSetAll$L() {
	long[] list = new long[3];
	list[0] = 0;
	list[1] = 1;
	list[2] = 2;

	Arrays.parallelSetAll(list, x -> x + 1);
	assertEquals(1, list[0]);
	assertEquals(2, list[1]);
	assertEquals(3, list[2]);

	try {
	Arrays.parallelSetAll(list, null);
	fail();
	} catch (NullPointerException expected) {
	}

	try {
	Arrays.parallelSetAll((long[]) null, (x -> x + 1));
	fail();
	} catch (NullPointerException expected) {
	}
	}

	/**
	* java.util.Arrays#setAll(double[], java.util.function.IntToDoubleFunction)
	*/
	public void test_setAll$D() {
	double[] list = new double[3];
	list[0] = 0.0d;
	list[1] = 1.0d;
	list[2] = 2.0d;

	Arrays.setAll(list, x -> x + 0.5);
	assertEquals(0.5d, list[0]);
	assertEquals(1.5d, list[1]);
	assertEquals(2.5d, list[2]);

	try {
	Arrays.setAll(list, null);
	fail();
	} catch (NullPointerException expected) {
	}

	try {
	Arrays.setAll((double[]) null, x -> x + 0.5);
	fail();
	} catch (NullPointerException expected) {
	}
	}

	/**
	* java.util.Arrays#parallelSetAll(double[], java.util.function.IntToDoubleFunction)
	*/
	public void test_parallelSetAll$D() {
	double[] list = new double[3];
	list[0] = 0.0d;
	list[1] = 1.0d;
	list[2] = 2.0d;

	Arrays.parallelSetAll(list, x -> x + 0.5);
	assertEquals(0.5d, list[0]);
	assertEquals(1.5d, list[1]);
	assertEquals(2.5d, list[2]);

	try {
	Arrays.parallelSetAll(list, null);
	fail();
	} catch (NullPointerException expected) {
	}

	try {
	Arrays.parallelSetAll((double[]) null, x -> x + 0.5);
	fail();
	} catch (NullPointerException expected) {
	}
	}

	/**
	* java.util.Array#setAll(T[], java.util.function.IntFunction<\? extends T>)
	*/
	public void test_setAll$T() {
	String[] strings = new String[3];
	strings[0] = "a";
	strings[0] = "b";
	strings[0] = "c";

	Arrays.setAll(strings, x -> "a" + x);
	assertEquals("a0", strings[0]);
	assertEquals("a1", strings[1]);
	assertEquals("a2", strings[2]);

	try {
	Arrays.setAll(strings, null);
	fail();
	} catch (NullPointerException expected) {
	}

	try {
	Arrays.setAll((String[]) null, x -> "a" + x);
	fail();
	} catch (NullPointerException expected) {
	}
	}

	/**
	* java.util.Array#parallelSetAll(T[], java.util.function.IntFunction<\? extends T>)
	*/
	public void test_parallelSetAll$T() {
	String[] strings = new String[3];
	strings[0] = "a";
	strings[0] = "b";
	strings[0] = "c";

	Arrays.parallelSetAll(strings, x -> "a" + x);
	assertEquals("a0", strings[0]);
	assertEquals("a1", strings[1]);
	assertEquals("a2", strings[2]);

	try {
	Arrays.parallelSetAll(strings, null);
	fail();
	} catch (NullPointerException expected) {
	}

	try {
	Arrays.parallelSetAll((String[]) null, x -> "a" + x);
	fail();
	} catch (NullPointerException expected) {
	}
	}

	/**
	* java.util.Array#parallelPrefix(int[], java.util.function.IntBinaryOperator)
	*/
	public void test_parallelPrefix$I() {
	// Get an arbitrary array of ints.
	Random rand = new Random(0);
	int[] list = new int[1000];
	for(int i = 0; i < list.length; ++i) {
	list[i] = rand.nextInt() % 1000; // Prevent overflow
	}

	int[] seqResult = list.clone();

	// Sequential solution
	for(int i = 0; i < seqResult.length - 1; ++i) {
	seqResult[i + 1] += seqResult[i];
	}

	Arrays.parallelPrefix(list, (x, y) -> x + y);
	assertTrue(Arrays.equals(seqResult, list));

	try {
	Arrays.parallelPrefix(list, null);
	fail();
	} catch (NullPointerException expected) {
	}

	try {
	Arrays.parallelPrefix((int[]) null, (x, y) -> x + y);
	fail();
	} catch (NullPointerException expected) {
	}
	}

	/**
	* java.util.Array#parallelPrefix(int[], int, int, java.util.function.IntBinaryOperator)
	*/
	public void test_parallelPrefix$III() {
	// Get an arbitrary array of ints.
	Random rand = new Random(0);
	int[] list = new int[1000];
	for(int i = 0; i < list.length; ++i) {
	list[i] = rand.nextInt() % 1000; // Prevent overflow
	}

	int begin = 100, end = 500;
	int[] seqResult = list.clone();

	// Sequential solution
	for(int i = begin; i < end - 1; ++i) {
	seqResult[i + 1] += seqResult[i];
	}

	Arrays.parallelPrefix(list, begin, end, (x, y) -> x + y);
	assertTrue(Arrays.equals(seqResult, list));

	try {
	Arrays.parallelPrefix(list, begin, end, null);
	fail();
	} catch (NullPointerException expected) {
	}

	try {
	Arrays.parallelPrefix((int[]) null, begin, end, (x, y) -> x + y);
	fail();
	} catch (NullPointerException expected) {
	}

	try {
	Arrays.parallelPrefix(list, end, begin, (x, y) -> x + y);
	fail();
	} catch (IllegalArgumentException expected) {
	}
	}

	/**
	* java.util.Array#parallelPrefix(long[], java.util.function.LongBinaryOperator)
	*/
	public void test_parallelPrefix$L() {
	// Get an arbitrary array of ints.
	Random rand = new Random(0);
	long[] list = new long[1000];
	for(int i = 0; i < list.length; ++i) {
	list[i] = rand.nextLong() % 1000000; // Prevent overflow
	}

	long[] seqResult = list.clone();

	// Sequential solution
	for(int i = 0; i < seqResult.length - 1; ++i) {
	seqResult[i + 1] += seqResult[i];
	}

	Arrays.parallelPrefix(list, (x, y) -> x + y);
	assertTrue(Arrays.equals(seqResult, list));

	try {
	Arrays.parallelPrefix(list, null);
	fail();
	} catch (NullPointerException expected) {
	}

	try {
	Arrays.parallelPrefix((long[]) null, (x, y) -> x + y);
	fail();
	} catch (NullPointerException expected) {
	}
	}

	/**
	* java.util.Array#parallelPrefix(long[], int, int, java.util.function.LongBinaryOperator)
	*/
	public void test_parallelPrefix$LII() {
	// Get an arbitrary array of ints.
	Random rand = new Random(0);
	long[] list = new long[1000];
	for(int i = 0; i < list.length; ++i) {
	list[i] = rand.nextLong() % 1000000; // Prevent overflow
	}

	int begin = 100, end = 500;
	long[] seqResult = list.clone();

	// Sequential solution
	for(int i = begin; i < end - 1; ++i) {
	seqResult[i + 1] += seqResult[i];
	}

	Arrays.parallelPrefix(list, begin, end, (x, y) -> x + y);
	assertTrue(Arrays.equals(seqResult, list));

	try {
	Arrays.parallelPrefix(list, begin, end, null);
	fail();
	} catch (NullPointerException expected) {
	}

	try {
	Arrays.parallelPrefix((long[]) null, begin, end, (x, y) -> x + y);
	fail();
	} catch (NullPointerException expected) {
	}

	try {
	Arrays.parallelPrefix(list, end, begin, (x, y) -> x + y);
	fail();
	} catch (IllegalArgumentException expected) {
	}
	}

	/**
	* java.util.Array#parallelPrefix(double[], java.util.function.DoubleBinaryOperator)
	*/
	public void test_parallelPrefix$D() {
	// Get an arbitrary array of ints.
	Random rand = new Random(0);
	double[] list = new double[1000];
	for(int i = 0; i < list.length; ++i) {
	list[i] = rand.nextDouble() * 1000;
	}

	double[] seqResult = list.clone();

	// Sequential solution
	for(int i = 0; i < seqResult.length - 1; ++i) {
	seqResult[i + 1] += seqResult[i];
	}

	Arrays.parallelPrefix(list, (x, y) -> x + y);

	// Parallel double arithmetic contains error, reduce to integer for comparison.
	int[] listInInt = Arrays.stream(list).mapToInt(x -> (int) x).toArray();
	int[] seqResultInInt = Arrays.stream(seqResult).mapToInt(x -> (int) x).toArray();
	assertTrue(Arrays.equals(seqResultInInt, listInInt));

	try {
	Arrays.parallelPrefix(list, null);
	fail();
	} catch (NullPointerException expected) {
	}

	try {
	Arrays.parallelPrefix((double[]) null, (x, y) -> x + y);
	fail();
	} catch (NullPointerException expected) {
	}
	}

	/**
	* java.util.Array#parallelPrefix(double[], int, int, java.util.function.DoubleBinaryOperator)
	*/
	public void test_parallelPrefix$DII() {
	// Get an arbitrary array of ints.
	Random rand = new Random(0);
	double[] list = new double[1000];
	for(int i = 0; i < list.length; ++i) {
	list[i] = rand.nextDouble() * 1000;
	}

	int begin = 100, end = 500;
	double[] seqResult = list.clone();

	// Sequential solution
	for(int i = begin; i < end - 1; ++i) {
	seqResult[i + 1] += seqResult[i];
	}

	Arrays.parallelPrefix(list, begin, end, (x, y) -> x + y);

	// Parallel double arithmetic contains error, reduce to integer for comparison.
	int[] listInInt = Arrays.stream(list).mapToInt(x -> (int) x).toArray();
	int[] seqResultInInt = Arrays.stream(seqResult).mapToInt(x -> (int) x).toArray();
	assertTrue(Arrays.equals(seqResultInInt, listInInt));

	try {
	Arrays.parallelPrefix(list, begin, end, null);
	fail();
	} catch (NullPointerException expected) {
	}

	try {
	Arrays.parallelPrefix((double[]) null, begin, end, (x, y) -> x + y);
	fail();
	} catch (NullPointerException expected) {
	}

	try {
	Arrays.parallelPrefix(list, end, begin, (x, y) -> x + y);
	fail();
	} catch (IllegalArgumentException expected) {
	}
	}

	/**
	* java.util.Array#parallelPrefix(T[], java.util.function.BinaryOperator<T>)
	*/
	public void test_parallelPrefix$T() {
	String[] strings = new String[3];
	strings[0] = "a";
	strings[1] = "b";
	strings[2] = "c";

	Arrays.parallelPrefix(strings, (x, y) -> x + y);
	assertEquals("a", strings[0]);
	assertEquals("ab", strings[1]);
	assertEquals("abc", strings[2]);

	try {
	Arrays.parallelPrefix(strings, null);
	fail();
	} catch (NullPointerException expected) {
	}

	try {
	Arrays.parallelPrefix((String[]) null, (x, y) -> x + y);
	fail();
	} catch (NullPointerException expected) {
	}
	}

	/**
	* java.util.Array#parallelPrefix(T[], int, int, java.util.function.BinaryOperator<T>)
	*/
	public void test_parallelPrefix$TII() {
	String[] strings = new String[5];
	strings[0] = "a";
	strings[1] = "b";
	strings[2] = "c";
	strings[3] = "d";
	strings[4] = "e";
	int begin = 1, end = 4;

	Arrays.parallelPrefix(strings, begin, end, (x, y) -> x + y);
	assertEquals("a", strings[0]);
	assertEquals("b", strings[1]);
	assertEquals("bc", strings[2]);
	assertEquals("bcd", strings[3]);
	assertEquals("e", strings[4]);

	try {
	Arrays.parallelPrefix(strings, begin, end, null);
	fail();
	} catch (NullPointerException expected) {
	}

	try {
	Arrays.parallelPrefix((String[]) null, begin, end, (x, y) -> x + y);
	fail();
	} catch (NullPointerException expected) {
	}

	try {
	Arrays.parallelPrefix(strings, end, begin, (x, y) -> x + y);
	fail();
	} catch (IllegalArgumentException expected) {
	}
	}
	}