Improved Android compatibility

pmml-evaluator/pom.xml

@@ -50,6 +50,12 @@
 			<artifactId>commons-math3</artifactId>
 		</dependency>
 
+		<dependency>
+			<groupId>org.codehaus.mojo</groupId>
+			<artifactId>animal-sniffer-annotations</artifactId>
+			<optional>true</optional>
+		</dependency>
+
 		<dependency>
 			<groupId>junit</groupId>
 			<artifactId>junit</artifactId>

pmml-evaluator/src/main/java/org/jpmml/evaluator/JDK8Map.java → pmml-evaluator/src/main/java/org/jpmml/evaluator/AndroidFieldValueMap.java

@@ -18,28 +18,38 @@
  */
 package org.jpmml.evaluator;
 
-import java.util.Map;
+import org.dmg.pmml.FieldName;
 
-interface JDK8Map<K, V> extends Map<K, V> {
+/**
+ * <p>
+ * Android 5.0 and 6.0 compatible implementation of {@link FieldValueMap}.
+ * </p>
+ */
+class AndroidFieldValueMap extends FieldValueMap {
+
+	AndroidFieldValueMap(){
+	}
+
+	AndroidFieldValueMap(int initialCapacity){
+		super(initialCapacity);
+	}
 
 	@Override
-	default
-	public V getOrDefault(Object key, V defaultValue){
+	public FieldValue getOrDefault(Object name, FieldValue defaultValue){
 
-		if(containsKey(key)){
-			return get(key);
+		if(containsKey(name)){
+			return get(name);
 		}
 
 		return defaultValue;
 	}
 
 	@Override
-	default
-	public V putIfAbsent(K key, V value){
-		V prevValue = get(key);
+	public FieldValue putIfAbsent(FieldName name, FieldValue value){
+		FieldValue prevValue = get(name);
 
 		if(prevValue == null){
-			return put(key, value);
+			return put(name, value);
 		}
 
 		return prevValue;

pmml-evaluator/src/main/java/org/jpmml/evaluator/EvaluationContext.java

@@ -38,18 +38,11 @@ public class EvaluationContext {
 
 
 	EvaluationContext(){
-		this.values = new FieldValueMap();
+		this.values = FieldValueMap.create();
 	}
 
 	EvaluationContext(int numberOfVisibleFields){
-
-		if(numberOfVisibleFields <= 256){
-			this.values = new FieldValueMap(Math.max(2 * numberOfVisibleFields, 16));
-		} else
-
-		{
-			this.values = new FieldValueMap(numberOfVisibleFields);
-		}
+		this.values = FieldValueMap.create(numberOfVisibleFields);
 	}
 
 	abstract

pmml-evaluator/src/main/java/org/jpmml/evaluator/FieldValueMap.java

@@ -19,10 +19,12 @@
 package org.jpmml.evaluator;
 
 import java.util.HashMap;
+import java.util.Map;
 
+import org.codehaus.mojo.animal_sniffer.IgnoreJRERequirement;
 import org.dmg.pmml.FieldName;
 
-class FieldValueMap extends HashMap<FieldName, FieldValue> implements JDK8Map<FieldName, FieldValue> {
+class FieldValueMap extends HashMap<FieldName, FieldValue> {
 
 	FieldValueMap(){
 	}
@@ -31,7 +33,61 @@ class FieldValueMap extends HashMap<FieldName, FieldValue> implements JDK8Map<Fi
 		super(capacity);
 	}
 
-	FieldValueMap(int capacity, float loadFactor){
-		super(capacity, loadFactor);
+	@Override
+	@IgnoreJRERequirement
+	public FieldValue getOrDefault(Object name, FieldValue defaultValue){
+		return super.getOrDefault(name, defaultValue);
+	}
+
+	@Override
+	@IgnoreJRERequirement
+	public FieldValue putIfAbsent(FieldName name, FieldValue value){
+		return super.putIfAbsent(name, value);
+	}
+
+	static
+	public FieldValueMap create(){
+
+		if(FieldValueMap.JDK8_API){
+			return new FieldValueMap();
+		}
+
+		return new AndroidFieldValueMap();
+	}
+
+	static
+	public FieldValueMap create(int numberOfVisibleFields){
+		int initialCapacity;
+
+		if(numberOfVisibleFields <= 256){
+			initialCapacity = Math.max(2 * numberOfVisibleFields, 16);
+		} else
+
+		{
+			initialCapacity = numberOfVisibleFields;
+		} // End if
+
+		if(FieldValueMap.JDK8_API){
+			return new FieldValueMap(initialCapacity);
+		}
+
+		return new AndroidFieldValueMap(initialCapacity);
+	}
+
+	protected static boolean JDK8_API;
+
+	static {
+		boolean jdk8_api;
+
+		try {
+			Map.class.getMethod("getOrDefault", Object.class, Object.class);
+			Map.class.getMethod("putIfAbsent", Object.class, Object.class);
+
+			jdk8_api = true;
+		} catch(ReflectiveOperationException roe){
+			jdk8_api = false;
+		}
+
+		JDK8_API = jdk8_api;
 	}
 }

pmml-evaluator/src/test/java/org/jpmml/evaluator/FieldValueMapTest.java

@@ -0,0 +1,65 @@
+/*
+ * Copyright (c) 2021 Villu Ruusmann
+ *
+ * This file is part of JPMML-Evaluator
+ *
+ * JPMML-Evaluator is free software: you can redistribute it and/or modify
+ * it under the terms of the GNU Affero General Public License as published by
+ * the Free Software Foundation, either version 3 of the License, or
+ * (at your option) any later version.
+ *
+ * JPMML-Evaluator is distributed in the hope that it will be useful,
+ * but WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+ * GNU Affero General Public License for more details.
+ *
+ * You should have received a copy of the GNU Affero General Public License
+ * along with JPMML-Evaluator.  If not, see <http://www.gnu.org/licenses/>.
+ */
+package org.jpmml.evaluator;
+
+import java.util.Map;
+
+import org.dmg.pmml.FieldName;
+import org.junit.Test;
+
+import static org.junit.Assert.assertNotNull;
+import static org.junit.Assert.assertTrue;
+import static org.junit.Assert.fail;
+
+public class FieldValueMapTest {
+
+	@Test
+	public void jdk8() throws Exception {
+		// Assume that unit tests are never run in non-JDK8 compatible environment
+		assertTrue(FieldValueMap.JDK8_API);
+
+		assertNotNull(Map.class.getMethod("getOrDefault", Object.class, Object.class));
+
+		try {
+			Map.class.getMethod("getOrDefault", Object.class, FieldValue.class);
+
+			fail();
+		} catch(ReflectiveOperationException roe){
+			// Ignored
+		} // End try
+
+		try {
+			Map.class.getMethod("getOrDefault", FieldName.class, FieldValue.class);
+
+			fail();
+		} catch(ReflectiveOperationException roe){
+			// Ignored
+		}
+
+		assertNotNull(Map.class.getMethod("putIfAbsent", Object.class, Object.class));
+
+		try {
+			Map.class.getMethod("putIfAbsent", FieldName.class, FieldValue.class);
+
+			fail();
+		} catch(ReflectiveOperationException roe){
+			// Ignored
+		}
+	}
+}

pom.xml

@@ -192,6 +192,12 @@
 				<version>[3.1, 3.6.1]</version>
 			</dependency>
 
+			<dependency>
+				<groupId>org.codehaus.mojo</groupId>
+				<artifactId>animal-sniffer-annotations</artifactId>
+				<version>1.19</version>
+			</dependency>
+
 			<dependency>
 				<groupId>org.slf4j</groupId>
 				<artifactId>slf4j-api</artifactId>