Merge "Partial Revert "Replace com.android.internal.util.Predicate with java.util.function.Predicate"" am: 621ebe692f am: a2c92b0b88

am: c1a93884dc

Change-Id: Icce543cd86f83bff8c2e80bf7ef492d22c9cf2dc

2 files changed, 157 insertions, 0 deletions

diff --git a/core/java/com/android/internal/util/Predicate.java b/core/java/com/android/internal/util/Predicate.java
new file mode 100644
index 000000000000..bc6d6b31dd28
--- /dev/null
+++ b/core/java/com/android/internal/util/Predicate.java
@@ -0,0 +1,32 @@
+/*
+ * Copyright (C) 2008 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 com.android.internal.util;
+
+/**
+ * A Predicate can determine a true or false value for any input of its
+ * parameterized type. For example, a {@code RegexPredicate} might implement
+ * {@code Predicate<String>}, and return true for any String that matches its
+ * given regular expression.
+ * <p/>
+ * <p/>
+ * Implementors of Predicate which may cause side effects upon evaluation are
+ * strongly encouraged to state this fact clearly in their API documentation.
+ */
+public interface Predicate<T> {
+
+    boolean apply(T t);
+}
diff --git a/core/java/com/android/internal/util/Predicates.java b/core/java/com/android/internal/util/Predicates.java
new file mode 100644
index 000000000000..c006564f129a
--- /dev/null
+++ b/core/java/com/android/internal/util/Predicates.java
@@ -0,0 +1,125 @@
+/*
+ * Copyright (C) 2008 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 com.android.internal.util;
+
+import java.util.Arrays;
+
+/**
+ * Predicates contains static methods for creating the standard set of
+ * {@code Predicate} objects.
+ */
+public class Predicates {
+
+    private Predicates() {
+    }
+
+    /**
+     * Returns a Predicate that evaluates to true iff each of its components
+     * evaluates to true.  The components are evaluated in order, and evaluation
+     * will be "short-circuited" as soon as the answer is determined.
+     */
+    public static <T> Predicate<T> and(Predicate<? super T>... components) {
+        return Predicates.<T>and(Arrays.asList(components));
+    }
+
+    /**
+     * Returns a Predicate that evaluates to true iff each of its components
+     * evaluates to true.  The components are evaluated in order, and evaluation
+     * will be "short-circuited" as soon as the answer is determined.  Does not
+     * defensively copy the iterable passed in, so future changes to it will alter
+     * the behavior of this Predicate. If components is empty, the returned
+     * Predicate will always evaluate to true.
+     */
+    public static <T> Predicate<T> and(Iterable<? extends Predicate<? super T>> components) {
+        return new AndPredicate(components);
+    }
+
+    /**
+     * Returns a Predicate that evaluates to true iff any one of its components
+     * evaluates to true.  The components are evaluated in order, and evaluation
+     * will be "short-circuited" as soon as the answer is determined.
+     */
+    public static <T> Predicate<T> or(Predicate<? super T>... components) {
+        return Predicates.<T>or(Arrays.asList(components));
+    }
+
+    /**
+     * Returns a Predicate that evaluates to true iff any one of its components
+     * evaluates to true.  The components are evaluated in order, and evaluation
+     * will be "short-circuited" as soon as the answer is determined.  Does not
+     * defensively copy the iterable passed in, so future changes to it will alter
+     * the behavior of this Predicate. If components is empty, the returned
+     * Predicate will always evaluate to false.
+     */
+    public static <T> Predicate<T> or(Iterable<? extends Predicate<? super T>> components) {
+        return new OrPredicate(components);
+    }
+
+    /**
+     * Returns a Predicate that evaluates to true iff the given Predicate
+     * evaluates to false.
+     */
+    public static <T> Predicate<T> not(Predicate<? super T> predicate) {
+        return new NotPredicate<T>(predicate);
+    }
+
+    private static class AndPredicate<T> implements Predicate<T> {
+        private final Iterable<? extends Predicate<? super T>> components;
+
+        private AndPredicate(Iterable<? extends Predicate<? super T>> components) {
+            this.components = components;
+        }
+
+        public boolean apply(T t) {
+            for (Predicate<? super T> predicate : components) {
+                if (!predicate.apply(t)) {
+                    return false;
+                }
+            }
+            return true;
+        }
+    }
+
+    private static class OrPredicate<T> implements Predicate<T> {
+        private final Iterable<? extends Predicate<? super T>> components;
+
+        private OrPredicate(Iterable<? extends Predicate<? super T>> components) {
+            this.components = components;
+        }
+
+        public boolean apply(T t) {
+            for (Predicate<? super T> predicate : components) {
+                if (predicate.apply(t)) {
+                    return true;
+                }
+            }
+            return false;
+        }
+    }
+
+    private static class NotPredicate<T> implements Predicate<T> {
+        private final Predicate<? super T> predicate;
+
+        private NotPredicate(Predicate<? super T> predicate) {
+            this.predicate = predicate;
+        }
+
+        public boolean apply(T t) {
+            return !predicate.apply(t);
+        }
+    }
+}