src/jdk.compiler/share/classes/com/sun/tools/javac/code/TypeTag.java
changeset 47216 71c04702a3d5
parent 42973 3795332b55c7
--- /dev/null	Thu Jan 01 00:00:00 1970 +0000
+++ b/src/jdk.compiler/share/classes/com/sun/tools/javac/code/TypeTag.java	Tue Sep 12 19:03:39 2017 +0200
@@ -0,0 +1,261 @@
+/*
+ * Copyright (c) 1999, 2014, Oracle and/or its affiliates. All rights reserved.
+ * DO NOT ALTER OR REMOVE COPYRIGHT NOTICES OR THIS FILE HEADER.
+ *
+ * This code is free software; you can redistribute it and/or modify it
+ * under the terms of the GNU General Public License version 2 only, as
+ * published by the Free Software Foundation.  Oracle designates this
+ * particular file as subject to the "Classpath" exception as provided
+ * by Oracle in the LICENSE file that accompanied this code.
+ *
+ * This code 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 General Public License
+ * version 2 for more details (a copy is included in the LICENSE file that
+ * accompanied this code).
+ *
+ * You should have received a copy of the GNU General Public License version
+ * 2 along with this work; if not, write to the Free Software Foundation,
+ * Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA.
+ *
+ * Please contact Oracle, 500 Oracle Parkway, Redwood Shores, CA 94065 USA
+ * or visit www.oracle.com if you need additional information or have any
+ * questions.
+ */
+
+package com.sun.tools.javac.code;
+
+import com.sun.source.tree.Tree.Kind;
+
+import javax.lang.model.type.TypeKind;
+
+import static com.sun.tools.javac.code.TypeTag.NumericClasses.*;
+
+/** An interface for type tag values, which distinguish between different
+ *  sorts of types.
+ *
+ *  <p><b>This is NOT part of any supported API.
+ *  If you write code that depends on this, you do so at your own risk.
+ *  This code and its internal interfaces are subject to change or
+ *  deletion without notice.</b>
+ */
+public enum TypeTag {
+    /** The tag of the basic type `byte'.
+     */
+    BYTE(BYTE_CLASS, BYTE_SUPERCLASSES, true),
+
+    /** The tag of the basic type `char'.
+     */
+    CHAR(CHAR_CLASS, CHAR_SUPERCLASSES, true),
+
+    /** The tag of the basic type `short'.
+     */
+    SHORT(SHORT_CLASS, SHORT_SUPERCLASSES, true),
+
+    /** The tag of the basic type `long'.
+     */
+    LONG(LONG_CLASS, LONG_SUPERCLASSES, true),
+
+    /** The tag of the basic type `float'.
+     */
+    FLOAT(FLOAT_CLASS, FLOAT_SUPERCLASSES, true),
+    /** The tag of the basic type `int'.
+     */
+    INT(INT_CLASS, INT_SUPERCLASSES, true),
+    /** The tag of the basic type `double'.
+     */
+    DOUBLE(DOUBLE_CLASS, DOUBLE_CLASS, true),
+    /** The tag of the basic type `boolean'.
+     */
+    BOOLEAN(0, 0, true),
+
+    /** The tag of the type `void'.
+     */
+    VOID,
+
+    /** The tag of all class and interface types.
+     */
+    CLASS,
+
+    /** The tag of all array types.
+     */
+    ARRAY,
+
+    /** The tag of all (monomorphic) method types.
+     */
+    METHOD,
+
+    /** The tag of all package "types".
+     */
+    PACKAGE,
+
+    /** The tag of all module "types".
+     */
+    MODULE,
+
+    /** The tag of all (source-level) type variables.
+     */
+    TYPEVAR,
+
+    /** The tag of all type arguments.
+     */
+    WILDCARD,
+
+    /** The tag of all polymorphic (method-) types.
+     */
+    FORALL,
+
+    /** The tag of deferred expression types in method context
+     */
+    DEFERRED,
+
+    /** The tag of the bottom type {@code <null>}.
+     */
+    BOT,
+
+    /** The tag of a missing type.
+     */
+    NONE,
+
+    /** The tag of the error type.
+     */
+    ERROR,
+
+    /** The tag of an unknown type
+     */
+    UNKNOWN,
+
+    /** The tag of all instantiatable type variables.
+     */
+    UNDETVAR,
+
+    /** Pseudo-types, these are special tags
+     */
+    UNINITIALIZED_THIS,
+
+    UNINITIALIZED_OBJECT;
+
+    final int superClasses;
+    final int numericClass;
+    final boolean isPrimitive;
+
+    private TypeTag() {
+        this(0, 0, false);
+    }
+
+    private TypeTag(int numericClass, int superClasses, boolean isPrimitive) {
+        this.superClasses = superClasses;
+        this.numericClass = numericClass;
+        this.isPrimitive = isPrimitive;
+    }
+
+    public static class NumericClasses {
+        public static final int BYTE_CLASS = 1;
+        public static final int CHAR_CLASS = 2;
+        public static final int SHORT_CLASS = 4;
+        public static final int INT_CLASS = 8;
+        public static final int LONG_CLASS = 16;
+        public static final int FLOAT_CLASS = 32;
+        public static final int DOUBLE_CLASS = 64;
+
+        static final int BYTE_SUPERCLASSES = BYTE_CLASS | SHORT_CLASS | INT_CLASS |
+                LONG_CLASS | FLOAT_CLASS | DOUBLE_CLASS;
+
+        static final int CHAR_SUPERCLASSES = CHAR_CLASS | INT_CLASS |
+                LONG_CLASS | FLOAT_CLASS | DOUBLE_CLASS;
+
+        static final int SHORT_SUPERCLASSES = SHORT_CLASS | INT_CLASS |
+                LONG_CLASS | FLOAT_CLASS | DOUBLE_CLASS;
+
+        static final int INT_SUPERCLASSES = INT_CLASS | LONG_CLASS | FLOAT_CLASS | DOUBLE_CLASS;
+
+        static final int LONG_SUPERCLASSES = LONG_CLASS | FLOAT_CLASS | DOUBLE_CLASS;
+
+        static final int FLOAT_SUPERCLASSES = FLOAT_CLASS | DOUBLE_CLASS;
+    }
+
+    public boolean isStrictSubRangeOf(TypeTag tag) {
+        /*  Please don't change the implementation of this method to call method
+         *  isSubRangeOf. Both methods are called from hotspot code, the current
+         *  implementation is better performance-wise than the commented modification.
+         */
+        return (this.superClasses & tag.numericClass) != 0 && this != tag;
+    }
+
+    public boolean isSubRangeOf(TypeTag tag) {
+        return (this.superClasses & tag.numericClass) != 0;
+    }
+
+    /** Returns the number of type tags.
+     */
+    public static int getTypeTagCount() {
+        // last two tags are not included in the total as long as they are pseudo-types
+        return (UNDETVAR.ordinal() + 1);
+    }
+
+    public Kind getKindLiteral() {
+        switch (this) {
+        case INT:
+            return Kind.INT_LITERAL;
+        case LONG:
+            return Kind.LONG_LITERAL;
+        case FLOAT:
+            return Kind.FLOAT_LITERAL;
+        case DOUBLE:
+            return Kind.DOUBLE_LITERAL;
+        case BOOLEAN:
+            return Kind.BOOLEAN_LITERAL;
+        case CHAR:
+            return Kind.CHAR_LITERAL;
+        case CLASS:
+            return Kind.STRING_LITERAL;
+        case BOT:
+            return Kind.NULL_LITERAL;
+        default:
+            throw new AssertionError("unknown literal kind " + this);
+        }
+    }
+
+    public TypeKind getPrimitiveTypeKind() {
+        switch (this) {
+        case BOOLEAN:
+            return TypeKind.BOOLEAN;
+        case BYTE:
+            return TypeKind.BYTE;
+        case SHORT:
+            return TypeKind.SHORT;
+        case INT:
+            return TypeKind.INT;
+        case LONG:
+            return TypeKind.LONG;
+        case CHAR:
+            return TypeKind.CHAR;
+        case FLOAT:
+            return TypeKind.FLOAT;
+        case DOUBLE:
+            return TypeKind.DOUBLE;
+        case VOID:
+            return TypeKind.VOID;
+        default:
+            throw new AssertionError("unknown primitive type " + this);
+        }
+    }
+
+    /** Returns true if the given value is within the allowed range for this type. */
+    public boolean checkRange(int value) {
+        switch (this) {
+            case BOOLEAN:
+                return 0 <= value && value <= 1;
+            case BYTE:
+                return Byte.MIN_VALUE <= value && value <= Byte.MAX_VALUE;
+            case CHAR:
+                return Character.MIN_VALUE <= value && value <= Character.MAX_VALUE;
+            case SHORT:
+                return Short.MIN_VALUE <= value && value <= Short.MAX_VALUE;
+            case INT:
+                return true;
+            default:
+                throw new AssertionError();
+        }
+    }
+}