Add utility to retrieve computers

Treiblesschorle · ctrueden · commit 70ddff6f94e4 · 2019-04-18T12:02:26.000-05:00
diff --git a/src/main/java/org/scijava/ops/util/Computers.java b/src/main/java/org/scijava/ops/util/Computers.java
@@ -0,0 +1,40 @@
+package org.scijava.ops.util;
+
+import java.lang.reflect.Type;
+
+import org.scijava.ops.BiComputer;
+import org.scijava.ops.Computer;
+import org.scijava.ops.Op;
+import org.scijava.ops.base.OpService;
+import org.scijava.ops.types.Nil;
+
+/**
+ * Utility providing adaptation between {@link Op} types.
+ */
+public class Computers {
+
+	private Computers() {
+		// NB: Prevent instantiation of utility class.
+	}
+
+	public static <I, O> Computer<I, O> unary(final OpService ops, final Class<? extends Op> opClass,
+			final Class<I> inputType, final Class<O> outputType) {
+		return ops.findOp( //
+				new Nil<Computer<I, O>>() {
+				}, //
+				new Type[] { opClass }, //
+				new Type[] { inputType, outputType }, //
+				outputType);
+	}
+
+	public static <I1, I2, O> BiComputer<I1, I2, O> binary(final OpService ops, final Class<? extends Op> opClass,
+			final Class<I1> input1Type, final Class<I2> input2Type, final Class<O> outputType) {
+		return ops.findOp( //
+				new Nil<BiComputer<I1, I2, O>>() {
+				}, //
+				new Type[] { opClass }, //
+				new Type[] { input1Type, input2Type, outputType }, //
+				outputType);
+	}
+
+}
diff --git a/src/test/java/org/scijava/ops/ComputersTest.java b/src/test/java/org/scijava/ops/ComputersTest.java
@@ -0,0 +1,58 @@
+/*
+ * #%L
+ * SciJava Operations: a framework for reusable algorithms.
+ * %%
+ * Copyright (C) 2018 SciJava developers.
+ * %%
+ * Redistribution and use in source and binary forms, with or without
+ * modification, are permitted provided that the following conditions are met:
+ *
+ * 1. Redistributions of source code must retain the above copyright notice,
+ *    this list of conditions and the following disclaimer.
+ * 2. Redistributions in binary form must reproduce the above copyright notice,
+ *    this list of conditions and the following disclaimer in the documentation
+ *    and/or other materials provided with the distribution.
+ *
+ * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS "AS IS"
+ * AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
+ * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
+ * ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT HOLDERS OR CONTRIBUTORS BE
+ * LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR
+ * CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF
+ * SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS
+ * INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN
+ * CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE)
+ * ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE
+ * POSSIBILITY OF SUCH DAMAGE.
+ * #L%
+ */
+
+package org.scijava.ops;
+
+import org.junit.Test;
+import org.scijava.ops.math.Add.MathAddOp;
+import org.scijava.ops.math.Sqrt.MathSqrtOp;
+import org.scijava.ops.util.Computers;
+
+public class ComputersTest extends AbstractTestEnvironment {
+
+	@Test
+	public void testUnaryComputers() {
+		Computer<double[], double[]> sqrtComputer = Computers.unary(ops, MathSqrtOp.class, double[].class,
+				double[].class);
+
+		double[] result = new double[3];
+		sqrtComputer.compute(new double[] { 4.0, 100.0, 25.0 }, result);
+		arrayEquals(result, 2d, 1d, 5d);
+	}
+
+	@Test
+	public void testBinaryComputers() {
+		BiComputer<double[], double[], double[]> addComputer = Computers.binary(ops, MathAddOp.class, double[].class,
+				double[].class, double[].class);
+
+		double[] result = new double[3];
+		addComputer.compute(new double[] { 4.0, 100.0, 25.0 }, new double[] { 4d, 10d, 1.5 }, result);
+		arrayEquals(result, 8d, 110d, 26.5);
+	}
+}
