/*
* Copyright (c) 2002, 2010, 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
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package com.sun.tools.javac.jvm;
import java.util.*;
import com.sun.tools.javac.code.Flags;
import com.sun.tools.javac.code.Symbol;
import com.sun.tools.javac.util.*;
import static com.sun.tools.javac.main.OptionName.*;
/** The classfile version target.
*
* <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 Target {
JDK1_1("1.1", 45, 3),
JDK1_2("1.2", 46, 0),
JDK1_3("1.3", 47, 0),
/** J2SE1.4 = Merlin. */
JDK1_4("1.4", 48, 0),
/** Support for the JSR14 prototype compiler (targeting 1.4 VMs
* augmented with a few support classes). This is a transitional
* option that will not be supported in the product. */
JSR14("jsr14", 48, 0),
/** The following are undocumented transitional targets that we
* had used to test VM fixes in update releases. We do not
* promise to retain support for them. */
JDK1_4_1("1.4.1", 48, 0),
JDK1_4_2("1.4.2", 48, 0),
/** Tiger. */
JDK1_5("1.5", 49, 0),
/** JDK 6. */
JDK1_6("1.6", 50, 0),
/** JDK 7. */
JDK1_7("1.7", 51, 0);
private static final Context.Key<Target> targetKey =
new Context.Key<Target>();
public static Target instance(Context context) {
Target instance = context.get(targetKey);
if (instance == null) {
Options options = Options.instance(context);
String targetString = options.get(TARGET);
if (targetString != null) instance = lookup(targetString);
if (instance == null) instance = DEFAULT;
context.put(targetKey, instance);
}
return instance;
}
private static Target MIN;
public static Target MIN() { return MIN; }
private static Target MAX;
public static Target MAX() { return MAX; }
private static Map<String,Target> tab = new HashMap<String,Target>();
static {
for (Target t : values()) {
if (MIN == null) MIN = t;
MAX = t;
tab.put(t.name, t);
}
tab.put("5", JDK1_5);
tab.put("6", JDK1_6);
tab.put("7", JDK1_7);
}
public final String name;
public final int majorVersion;
public final int minorVersion;
private Target(String name, int majorVersion, int minorVersion) {
this.name = name;
this.majorVersion = majorVersion;
this.minorVersion = minorVersion;
}
public static final Target DEFAULT = JDK1_7;
public static Target lookup(String name) {
return tab.get(name);
}
/** In -target 1.1 and earlier, the compiler is required to emit
* synthetic method definitions in abstract classes for interface
* methods that are not overridden. We call them "Miranda" methods.
*/
public boolean requiresIproxy() {
return compareTo(JDK1_1) <= 0;
}
/** Beginning in 1.4, we take advantage of the possibility of emitting
* code to initialize fields before calling the superclass constructor.
* This is allowed by the VM spec, but the verifier refused to allow
* it until 1.4. This is necesary to translate some code involving
* inner classes. See, for example, 4030374.
*/
public boolean initializeFieldsBeforeSuper() {
return compareTo(JDK1_4) >= 0;
}
/** Beginning with -target 1.2 we obey the JLS rules for binary
* compatibility, emitting as the qualifying type of a reference
* to a method or field the type of the qualifier. In earlier
* targets we use as the qualifying type the class in which the
* member was found. The following methods named
* *binaryCompatibility() indicate places where we vary from this
* general rule. */
public boolean obeyBinaryCompatibility() {
return compareTo(JDK1_2) >= 0;
}
/** Starting in 1.5, the compiler uses an array type as
* the qualifier for method calls (such as clone) where required by
* the language and VM spec. Earlier versions of the compiler
* qualified them by Object.
*/
public boolean arrayBinaryCompatibility() {
return compareTo(JDK1_5) >= 0;
}
/** Beginning after 1.2, we follow the binary compatibility rules for
* interface fields. The 1.2 VMs had bugs handling interface fields
* when compiled using binary compatibility (see 4400598), so this is
* an accommodation to them.
*/
public boolean interfaceFieldsBinaryCompatibility() {
return compareTo(JDK1_2) > 0;
}
/** Beginning in -target 1.5, we follow the binary compatibility
* rules for interface methods that redefine Object methods.
* Earlier VMs had bugs handling such methods compiled using binary
* compatibility (see 4392595, 4398791, 4392595, 4400415).
* The VMs were fixed during or soon after 1.4. See 4392595.
*/
public boolean interfaceObjectOverridesBinaryCompatibility() {
return compareTo(JDK1_5) >= 0;
}
/** Beginning in -target 1.4.2, we make synthetic variables
* package-private instead of private. This is to prevent the
* necessity of access methods, which effectively relax the
* protection of the field but bloat the class files and affect
* execution.
*/
public boolean usePrivateSyntheticFields() {
return compareTo(JDK1_4_2) < 0;
}
/** Sometimes we need to create a field to cache a value like a
* class literal of the assertions flag. In -target 1.4.2 and
* later we create a new synthetic class for this instead of
* using the outermost class. See 4401576.
*/
public boolean useInnerCacheClass() {
return compareTo(JDK1_4_2) >= 0;
}
/** Return true if cldc-style stack maps need to be generated. */
public boolean generateCLDCStackmap() {
return false;
}
/** Beginning in -target 6, we generate stackmap attribute in
* compact format. */
public boolean generateStackMapTable() {
return compareTo(JDK1_6) >= 0;
}
/** Beginning in -target 6, package-info classes are marked synthetic.
*/
public boolean isPackageInfoSynthetic() {
return compareTo(JDK1_6) >= 0;
}
/** Do we generate "empty" stackmap slots after double and long?
*/
public boolean generateEmptyAfterBig() {
return false;
}
/** Beginning in 1.5, we have an unsynchronized version of
* StringBuffer called StringBuilder that can be used by the
* compiler for string concatenation.
*/
public boolean useStringBuilder() {
return compareTo(JDK1_5) >= 0;
}
/** Beginning in 1.5, we have flag bits we can use instead of
* marker attributes.
*/
public boolean useSyntheticFlag() {
return compareTo(JDK1_5) >= 0;
}
public boolean useEnumFlag() {
return compareTo(JDK1_5) >= 0;
}
public boolean useAnnotationFlag() {
return compareTo(JDK1_5) >= 0;
}
public boolean useVarargsFlag() {
return compareTo(JDK1_5) >= 0;
}
public boolean useBridgeFlag() {
return compareTo(JDK1_5) >= 0;
}
/** Return the character to be used in constructing synthetic
* identifiers, where not specified by the JLS.
*/
public char syntheticNameChar() {
return '$';
}
/** Does the VM have direct support for class literals?
*/
public boolean hasClassLiterals() {
return compareTo(JDK1_5) >= 0;
}
/** Does the VM support an invokedynamic instruction?
*/
public boolean hasInvokedynamic() {
return compareTo(JDK1_7) >= 0;
}
/** Does the VM support polymorphic method handle invocation?
* Affects the linkage information output to the classfile.
* An alias for {@code hasInvokedynamic}, since all the JSR 292 features appear together.
*/
public boolean hasMethodHandles() {
return hasInvokedynamic();
}
/** Although we may not have support for class literals, should we
* avoid initializing the class that the literal refers to?
* See 4468823
*/
public boolean classLiteralsNoInit() {
return compareTo(JDK1_4_2) >= 0;
}
/** Although we may not have support for class literals, when we
* throw a NoClassDefFoundError, should we initialize its cause?
*/
public boolean hasInitCause() {
return compareTo(JDK1_4) >= 0;
}
/** For bootstrapping, we use J2SE1.4's wrapper class constructors
* to implement boxing.
*/
public boolean boxWithConstructors() {
return compareTo(JDK1_5) < 0;
}
/** For bootstrapping, we use J2SE1.4's java.util.Collection
* instead of java.lang.Iterable.
*/
public boolean hasIterable() {
return compareTo(JDK1_5) >= 0;
}
/** For bootstrapping javac only, we do without java.lang.Enum if
* necessary.
*/
public boolean compilerBootstrap(Symbol c) {
return
this == JSR14 &&
(c.flags() & Flags.ENUM) != 0 &&
c.flatName().toString().startsWith("com.sun.tools.")
// && !Target.class.getSuperclass().getName().equals("java.lang.Enum")
;
}
/** In J2SE1.5.0, we introduced the "EnclosingMethod" attribute
* for improved reflection support.
*/
public boolean hasEnclosingMethodAttribute() {
return compareTo(JDK1_5) >= 0 || this == JSR14;
}
}