aoqi@0: /*
aoqi@0:  * Copyright (c) 2002, 2013, Oracle and/or its affiliates. All rights reserved.
aoqi@0:  * DO NOT ALTER OR REMOVE COPYRIGHT NOTICES OR THIS FILE HEADER.
aoqi@0:  *
aoqi@0:  * This code is free software; you can redistribute it and/or modify it
aoqi@0:  * under the terms of the GNU General Public License version 2 only, as
aoqi@0:  * published by the Free Software Foundation.  Oracle designates this
aoqi@0:  * particular file as subject to the "Classpath" exception as provided
aoqi@0:  * by Oracle in the LICENSE file that accompanied this code.
aoqi@0:  *
aoqi@0:  * This code is distributed in the hope that it will be useful, but WITHOUT
aoqi@0:  * ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or
aoqi@0:  * FITNESS FOR A PARTICULAR PURPOSE.  See the GNU General Public License
aoqi@0:  * version 2 for more details (a copy is included in the LICENSE file that
aoqi@0:  * accompanied this code).
aoqi@0:  *
aoqi@0:  * You should have received a copy of the GNU General Public License version
aoqi@0:  * 2 along with this work; if not, write to the Free Software Foundation,
aoqi@0:  * Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA.
aoqi@0:  *
aoqi@0:  * Please contact Oracle, 500 Oracle Parkway, Redwood Shores, CA 94065 USA
aoqi@0:  * or visit www.oracle.com if you need additional information or have any
aoqi@0:  * questions.
aoqi@0:  */
aoqi@0: 
aoqi@0: package com.sun.tools.javac.jvm;
aoqi@0: 
aoqi@0: import java.util.*;
aoqi@0: 
aoqi@0: import com.sun.tools.javac.code.Flags;
aoqi@0: import com.sun.tools.javac.code.Symbol;
aoqi@0: import com.sun.tools.javac.util.*;
aoqi@0: 
aoqi@0: import static com.sun.tools.javac.main.Option.TARGET;
aoqi@0: 
aoqi@0: /** The classfile version target.
aoqi@0:  *
aoqi@0:  *  <p><b>This is NOT part of any supported API.
aoqi@0:  *  If you write code that depends on this, you do so at your own risk.
aoqi@0:  *  This code and its internal interfaces are subject to change or
aoqi@0:  *  deletion without notice.</b>
aoqi@0:  */
aoqi@0: public enum Target {
aoqi@0:     JDK1_1("1.1", 45, 3),
aoqi@0:     JDK1_2("1.2", 46, 0),
aoqi@0:     JDK1_3("1.3", 47, 0),
aoqi@0: 
aoqi@0:     /** J2SE1.4 = Merlin. */
aoqi@0:     JDK1_4("1.4", 48, 0),
aoqi@0: 
aoqi@0:     /** Tiger. */
aoqi@0:     JDK1_5("1.5", 49, 0),
aoqi@0: 
aoqi@0:     /** JDK 6. */
aoqi@0:     JDK1_6("1.6", 50, 0),
aoqi@0: 
aoqi@0:     /** JDK 7. */
aoqi@0:     JDK1_7("1.7", 51, 0),
aoqi@0: 
aoqi@0:     /** JDK 8. */
aoqi@0:     JDK1_8("1.8", 52, 0);
aoqi@0: 
aoqi@0:     private static final Context.Key<Target> targetKey =
aoqi@0:         new Context.Key<Target>();
aoqi@0: 
aoqi@0:     public static Target instance(Context context) {
aoqi@0:         Target instance = context.get(targetKey);
aoqi@0:         if (instance == null) {
aoqi@0:             Options options = Options.instance(context);
aoqi@0:             String targetString = options.get(TARGET);
aoqi@0:             if (targetString != null) instance = lookup(targetString);
aoqi@0:             if (instance == null) instance = DEFAULT;
aoqi@0:             context.put(targetKey, instance);
aoqi@0:         }
aoqi@0:         return instance;
aoqi@0:     }
aoqi@0: 
aoqi@0:     private static final Target MIN = values()[0];
aoqi@0:     public static Target MIN() { return MIN; }
aoqi@0: 
aoqi@0:     private static final Target MAX = values()[values().length - 1];
aoqi@0:     public static Target MAX() { return MAX; }
aoqi@0: 
aoqi@0:     private static final Map<String,Target> tab = new HashMap<String,Target>();
aoqi@0:     static {
aoqi@0:         for (Target t : values()) {
aoqi@0:             tab.put(t.name, t);
aoqi@0:         }
aoqi@0:         tab.put("5", JDK1_5);
aoqi@0:         tab.put("6", JDK1_6);
aoqi@0:         tab.put("7", JDK1_7);
aoqi@0:         tab.put("8", JDK1_8);
aoqi@0:     }
aoqi@0: 
aoqi@0:     public final String name;
aoqi@0:     public final int majorVersion;
aoqi@0:     public final int minorVersion;
aoqi@0:     private Target(String name, int majorVersion, int minorVersion) {
aoqi@0:         this.name = name;
aoqi@0:         this.majorVersion = majorVersion;
aoqi@0:         this.minorVersion = minorVersion;
aoqi@0:     }
aoqi@0: 
aoqi@0:     public static final Target DEFAULT = JDK1_8;
aoqi@0: 
aoqi@0:     public static Target lookup(String name) {
aoqi@0:         return tab.get(name);
aoqi@0:     }
aoqi@0: 
aoqi@0:     /** In -target 1.1 and earlier, the compiler is required to emit
aoqi@0:      *  synthetic method definitions in abstract classes for interface
aoqi@0:      *  methods that are not overridden.  We call them "Miranda" methods.
aoqi@0:      */
aoqi@0:     public boolean requiresIproxy() {
aoqi@0:         return compareTo(JDK1_1) <= 0;
aoqi@0:     }
aoqi@0: 
aoqi@0:     /** Beginning in 1.4, we take advantage of the possibility of emitting
aoqi@0:      *  code to initialize fields before calling the superclass constructor.
aoqi@0:      *  This is allowed by the VM spec, but the verifier refused to allow
aoqi@0:      *  it until 1.4.  This is necesary to translate some code involving
aoqi@0:      *  inner classes.  See, for example, 4030374.
aoqi@0:      */
aoqi@0:     public boolean initializeFieldsBeforeSuper() {
aoqi@0:         return compareTo(JDK1_4) >= 0;
aoqi@0:     }
aoqi@0: 
aoqi@0:     /** Beginning with -target 1.2 we obey the JLS rules for binary
aoqi@0:      *  compatibility, emitting as the qualifying type of a reference
aoqi@0:      *  to a method or field the type of the qualifier.  In earlier
aoqi@0:      *  targets we use as the qualifying type the class in which the
aoqi@0:      *  member was found.  The following methods named
aoqi@0:      *  *binaryCompatibility() indicate places where we vary from this
aoqi@0:      *  general rule. */
aoqi@0:     public boolean obeyBinaryCompatibility() {
aoqi@0:         return compareTo(JDK1_2) >= 0;
aoqi@0:     }
aoqi@0: 
aoqi@0:     /** Starting in 1.5, the compiler uses an array type as
aoqi@0:      *  the qualifier for method calls (such as clone) where required by
aoqi@0:      *  the language and VM spec.  Earlier versions of the compiler
aoqi@0:      *  qualified them by Object.
aoqi@0:      */
aoqi@0:     public boolean arrayBinaryCompatibility() {
aoqi@0:         return compareTo(JDK1_5) >= 0;
aoqi@0:     }
aoqi@0: 
aoqi@0:     /** Beginning after 1.2, we follow the binary compatibility rules for
aoqi@0:      *  interface fields.  The 1.2 VMs had bugs handling interface fields
aoqi@0:      *  when compiled using binary compatibility (see 4400598), so this is
aoqi@0:      *  an accommodation to them.
aoqi@0:      */
aoqi@0:     public boolean interfaceFieldsBinaryCompatibility() {
aoqi@0:         return compareTo(JDK1_2) > 0;
aoqi@0:     }
aoqi@0: 
aoqi@0:     /** Beginning in -target 1.5, we follow the binary compatibility
aoqi@0:      *  rules for interface methods that redefine Object methods.
aoqi@0:      *  Earlier VMs had bugs handling such methods compiled using binary
aoqi@0:      *  compatibility (see 4392595, 4398791, 4392595, 4400415).
aoqi@0:      *  The VMs were fixed during or soon after 1.4.  See 4392595.
aoqi@0:      */
aoqi@0:     public boolean interfaceObjectOverridesBinaryCompatibility() {
aoqi@0:         return compareTo(JDK1_5) >= 0;
aoqi@0:     }
aoqi@0: 
aoqi@0:     /** Beginning in -target 1.5, we make synthetic variables
aoqi@0:      *  package-private instead of private.  This is to prevent the
aoqi@0:      *  necessity of access methods, which effectively relax the
aoqi@0:      *  protection of the field but bloat the class files and affect
aoqi@0:      *  execution.
aoqi@0:      */
aoqi@0:     public boolean usePrivateSyntheticFields() {
aoqi@0:         return compareTo(JDK1_5) < 0;
aoqi@0:     }
aoqi@0: 
aoqi@0:     /** Sometimes we need to create a field to cache a value like a
aoqi@0:      *  class literal of the assertions flag.  In -target 1.5 and
aoqi@0:      *  later we create a new synthetic class for this instead of
aoqi@0:      *  using the outermost class.  See 4401576.
aoqi@0:      */
aoqi@0:     public boolean useInnerCacheClass() {
aoqi@0:         return compareTo(JDK1_5) >= 0;
aoqi@0:     }
aoqi@0: 
aoqi@0:     /** Return true if cldc-style stack maps need to be generated. */
aoqi@0:     public boolean generateCLDCStackmap() {
aoqi@0:         return false;
aoqi@0:     }
aoqi@0: 
aoqi@0:     /** Beginning in -target 6, we generate stackmap attribute in
aoqi@0:      *  compact format. */
aoqi@0:     public boolean generateStackMapTable() {
aoqi@0:         return compareTo(JDK1_6) >= 0;
aoqi@0:     }
aoqi@0: 
aoqi@0:     /** Beginning in -target 6, package-info classes are marked synthetic.
aoqi@0:      */
aoqi@0:     public boolean isPackageInfoSynthetic() {
aoqi@0:         return compareTo(JDK1_6) >= 0;
aoqi@0:     }
aoqi@0: 
aoqi@0:     /** Do we generate "empty" stackmap slots after double and long?
aoqi@0:      */
aoqi@0:     public boolean generateEmptyAfterBig() {
aoqi@0:         return false;
aoqi@0:     }
aoqi@0: 
aoqi@0:     /** Beginning in 1.5, we have an unsynchronized version of
aoqi@0:      *  StringBuffer called StringBuilder that can be used by the
aoqi@0:      *  compiler for string concatenation.
aoqi@0:      */
aoqi@0:     public boolean useStringBuilder() {
aoqi@0:         return compareTo(JDK1_5) >= 0;
aoqi@0:     }
aoqi@0: 
aoqi@0:     /** Beginning in 1.5, we have flag bits we can use instead of
aoqi@0:      *  marker attributes.
aoqi@0:      */
aoqi@0:     public boolean useSyntheticFlag() {
aoqi@0:         return compareTo(JDK1_5) >= 0;
aoqi@0:     }
aoqi@0:     public boolean useEnumFlag() {
aoqi@0:         return compareTo(JDK1_5) >= 0;
aoqi@0:     }
aoqi@0:     public boolean useAnnotationFlag() {
aoqi@0:         return compareTo(JDK1_5) >= 0;
aoqi@0:     }
aoqi@0:     public boolean useVarargsFlag() {
aoqi@0:         return compareTo(JDK1_5) >= 0;
aoqi@0:     }
aoqi@0:     public boolean useBridgeFlag() {
aoqi@0:         return compareTo(JDK1_5) >= 0;
aoqi@0:     }
aoqi@0: 
aoqi@0:     /** Return the character to be used in constructing synthetic
aoqi@0:      *  identifiers, where not specified by the JLS.
aoqi@0:      */
aoqi@0:     public char syntheticNameChar() {
aoqi@0:         return '$';
aoqi@0:     }
aoqi@0: 
aoqi@0:     /** Does the VM have direct support for class literals?
aoqi@0:      */
aoqi@0:     public boolean hasClassLiterals() {
aoqi@0:         return compareTo(JDK1_5) >= 0;
aoqi@0:     }
aoqi@0: 
aoqi@0:     /** Does the VM support an invokedynamic instruction?
aoqi@0:      */
aoqi@0:     public boolean hasInvokedynamic() {
aoqi@0:         return compareTo(JDK1_7) >= 0;
aoqi@0:     }
aoqi@0: 
aoqi@0:     /** Does the VM support polymorphic method handle invocation?
aoqi@0:      *  Affects the linkage information output to the classfile.
aoqi@0:      *  An alias for {@code hasInvokedynamic}, since all the JSR 292 features appear together.
aoqi@0:      */
aoqi@0:     public boolean hasMethodHandles() {
aoqi@0:         return hasInvokedynamic();
aoqi@0:     }
aoqi@0: 
aoqi@0:     /** Although we may not have support for class literals, should we
aoqi@0:      *  avoid initializing the class that the literal refers to?
aoqi@0:      *  See 4468823
aoqi@0:      */
aoqi@0:     public boolean classLiteralsNoInit() {
aoqi@0:         return compareTo(JDK1_5) >= 0;
aoqi@0:     }
aoqi@0: 
aoqi@0:     /** Although we may not have support for class literals, when we
aoqi@0:      *  throw a NoClassDefFoundError, should we initialize its cause?
aoqi@0:      */
aoqi@0:     public boolean hasInitCause() {
aoqi@0:         return compareTo(JDK1_4) >= 0;
aoqi@0:     }
aoqi@0: 
aoqi@0:     /** For bootstrapping, we use J2SE1.4's wrapper class constructors
aoqi@0:      *  to implement boxing.
aoqi@0:      */
aoqi@0:     public boolean boxWithConstructors() {
aoqi@0:         return compareTo(JDK1_5) < 0;
aoqi@0:     }
aoqi@0: 
aoqi@0:     /** For bootstrapping, we use J2SE1.4's java.util.Collection
aoqi@0:      *  instead of java.lang.Iterable.
aoqi@0:      */
aoqi@0:     public boolean hasIterable() {
aoqi@0:         return compareTo(JDK1_5) >= 0;
aoqi@0:     }
aoqi@0: 
aoqi@0:     /** In J2SE1.5.0, we introduced the "EnclosingMethod" attribute
aoqi@0:      *  for improved reflection support.
aoqi@0:      */
aoqi@0:     public boolean hasEnclosingMethodAttribute() {
aoqi@0:         return compareTo(JDK1_5) >= 0;
aoqi@0:     }
aoqi@0: }