langtools/src/share/classes/com/sun/tools/javac/code/SymbolMetadata.java - platform/libcore - Git at Google

 /*
  * Copyright (c) 2012, 2013, 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 java.util.Map;

 import javax.tools.JavaFileObject;

 import com.sun.tools.javac.comp.Annotate;
 import com.sun.tools.javac.comp.AttrContext;
 import com.sun.tools.javac.comp.Env;
 import com.sun.tools.javac.util.*;
 import com.sun.tools.javac.util.Assert;
 import com.sun.tools.javac.util.List;
 import com.sun.tools.javac.util.Log;
 import com.sun.tools.javac.util.Pair;
 import static com.sun.tools.javac.code.Kinds.PCK;

 /**
  * Container for all annotations (attributes in javac) on a Symbol.
  *
  * This class is explicitly mutable. Its contents will change when attributes
  * are annotated onto the Symbol. However this class depends on the facts that
  * List (in javac) is immutable.
  *
  * An instance of this class can be in one of three states:
  *
  * NOT_STARTED indicates that the Symbol this instance belongs to has not been
  * annotated (yet). Specifically if the declaration is not annotated this
  * instance will never move past NOT_STARTED. You can never go back to
  * NOT_STARTED.
  *
  * IN_PROGRESS annotations have been found on the declaration. Will be processed
  * later. You can reset to IN_PROGRESS. While IN_PROGRESS you can set the list
  * of attributes (and this moves out of the IN_PROGRESS state).
  *
  * "unnamed" this SymbolMetadata contains some attributes, possibly the final set.
  * While in this state you can only prepend or append to the attributes not set
  * it directly. You can also move back to the IN_PROGRESS state using reset().
  *
  * <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 class SymbolMetadata {

     private static final List<Attribute.Compound> DECL_NOT_STARTED = List.of(null);
     private static final List<Attribute.Compound> DECL_IN_PROGRESS = List.of(null);

     /*
      * This field should never be null
      */
     private List<Attribute.Compound> attributes = DECL_NOT_STARTED;

     /*
      * Type attributes for this symbol.
      * This field should never be null.
      */
     private List<Attribute.TypeCompound> type_attributes = List.<Attribute.TypeCompound>nil();

     /*
      * Type attributes of initializers in this class.
      * Unused if the current symbol is not a ClassSymbol.
      */
     private List<Attribute.TypeCompound> init_type_attributes = List.<Attribute.TypeCompound>nil();

     /*
      * Type attributes of class initializers in this class.
      * Unused if the current symbol is not a ClassSymbol.
      */
     private List<Attribute.TypeCompound> clinit_type_attributes = List.<Attribute.TypeCompound>nil();

     /*
      * The Symbol this SymbolMetadata instance belongs to
      */
     private final Symbol sym;

     public SymbolMetadata(Symbol sym) {
         this.sym = sym;
     }

     public List<Attribute.Compound> getDeclarationAttributes() {
         return filterDeclSentinels(attributes);
     }

     public List<Attribute.TypeCompound> getTypeAttributes() {
         return type_attributes;
     }

     public List<Attribute.TypeCompound> getInitTypeAttributes() {
         return init_type_attributes;
     }

     public List<Attribute.TypeCompound> getClassInitTypeAttributes() {
         return clinit_type_attributes;
     }

     public void setDeclarationAttributes(List<Attribute.Compound> a) {
         Assert.check(pendingCompletion() || !isStarted());
         if (a == null) {
             throw new NullPointerException();
         }
         attributes = a;
     }

     public void setTypeAttributes(List<Attribute.TypeCompound> a) {
         if (a == null) {
             throw new NullPointerException();
         }
         type_attributes = a;
     }

     public void setInitTypeAttributes(List<Attribute.TypeCompound> a) {
         if (a == null) {
             throw new NullPointerException();
         }
         init_type_attributes = a;
     }

     public void setClassInitTypeAttributes(List<Attribute.TypeCompound> a) {
         if (a == null) {
             throw new NullPointerException();
         }
         clinit_type_attributes = a;
     }

     public void setAttributes(SymbolMetadata other) {
         if (other == null) {
             throw new NullPointerException();
         }
         setDeclarationAttributes(other.getDeclarationAttributes());
         setTypeAttributes(other.getTypeAttributes());
         setInitTypeAttributes(other.getInitTypeAttributes());
         setClassInitTypeAttributes(other.getClassInitTypeAttributes());
     }

     public void setDeclarationAttributesWithCompletion(final Annotate.AnnotateRepeatedContext<Attribute.Compound> ctx) {
         Assert.check(pendingCompletion() || (!isStarted() && sym.kind == PCK));
         this.setDeclarationAttributes(getAttributesForCompletion(ctx));
     }

     public void appendTypeAttributesWithCompletion(final Annotate.AnnotateRepeatedContext<Attribute.TypeCompound> ctx) {
         this.appendUniqueTypes(getAttributesForCompletion(ctx));
     }

     private <T extends Attribute.Compound> List<T> getAttributesForCompletion(
             final Annotate.AnnotateRepeatedContext<T> ctx) {

         Map<Symbol.TypeSymbol, ListBuffer<T>> annotated = ctx.annotated;
         boolean atLeastOneRepeated = false;
         List<T> buf = List.<T>nil();
         for (ListBuffer<T> lb : annotated.values()) {
             if (lb.size() == 1) {
                 buf = buf.prepend(lb.first());
             } else { // repeated
                 // This will break when other subtypes of Attributs.Compound
                 // are introduced, because PlaceHolder is a subtype of TypeCompound.
                 T res;
                 @SuppressWarnings("unchecked")
                 T ph = (T) new Placeholder<>(ctx, lb.toList(), sym);
                 res = ph;
                 buf = buf.prepend(res);
                 atLeastOneRepeated = true;
             }
         }

         if (atLeastOneRepeated) {
             // The Symbol s is now annotated with a combination of
             // finished non-repeating annotations and placeholders for
             // repeating annotations.
             //
             // We need to do this in two passes because when creating
             // a container for a repeating annotation we must
             // guarantee that the @Repeatable on the
             // contained annotation is fully annotated
             //
             // The way we force this order is to do all repeating
             // annotations in a pass after all non-repeating are
             // finished. This will work because @Repeatable
             // is non-repeating and therefore will be annotated in the
             // fist pass.

             // Queue a pass that will replace Attribute.Placeholders
             // with Attribute.Compound (made from synthesized containers).
             ctx.annotateRepeated(new Annotate.Worker() {
                 @Override
                 public String toString() {
                     return "repeated annotation pass of: " + sym + " in: " + sym.owner;
                 }

                 @Override
                 public void run() {
                     complete(ctx);
                 }
             });
         }
         // Add non-repeating attributes
         return buf.reverse();
     }

     public SymbolMetadata reset() {
         attributes = DECL_IN_PROGRESS;
         return this;
     }

     public boolean isEmpty() {
         return !isStarted()
                 || pendingCompletion()
                 || attributes.isEmpty();
     }

     public boolean isTypesEmpty() {
         return type_attributes.isEmpty();
     }

     public boolean pendingCompletion() {
         return attributes == DECL_IN_PROGRESS;
     }

     public SymbolMetadata append(List<Attribute.Compound> l) {
         attributes = filterDeclSentinels(attributes);

         if (l.isEmpty()) {
             // no-op
         } else if (attributes.isEmpty()) {
             attributes = l;
         } else {
             attributes = attributes.appendList(l);
         }
         return this;
     }

     public SymbolMetadata appendUniqueTypes(List<Attribute.TypeCompound> l) {
         if (l.isEmpty()) {
             // no-op
         } else if (type_attributes.isEmpty()) {
             type_attributes = l;
         } else {
             // TODO: in case we expect a large number of annotations, this
             // might be inefficient.
             for (Attribute.TypeCompound tc : l) {
                 if (!type_attributes.contains(tc))
                     type_attributes = type_attributes.append(tc);
             }
         }
         return this;
     }

     public SymbolMetadata appendInitTypeAttributes(List<Attribute.TypeCompound> l) {
         if (l.isEmpty()) {
             // no-op
         } else if (init_type_attributes.isEmpty()) {
             init_type_attributes = l;
         } else {
             init_type_attributes = init_type_attributes.appendList(l);
         }
         return this;
     }

     public SymbolMetadata appendClassInitTypeAttributes(List<Attribute.TypeCompound> l) {
         if (l.isEmpty()) {
             // no-op
         } else if (clinit_type_attributes.isEmpty()) {
             clinit_type_attributes = l;
         } else {
             clinit_type_attributes = clinit_type_attributes.appendList(l);
         }
         return this;
     }

     public SymbolMetadata prepend(List<Attribute.Compound> l) {
         attributes = filterDeclSentinels(attributes);

         if (l.isEmpty()) {
             // no-op
         } else if (attributes.isEmpty()) {
             attributes = l;
         } else {
             attributes = attributes.prependList(l);
         }
         return this;
     }

     private List<Attribute.Compound> filterDeclSentinels(List<Attribute.Compound> a) {
         return (a == DECL_IN_PROGRESS || a == DECL_NOT_STARTED)
                 ? List.<Attribute.Compound>nil()
                 : a;
     }

     private boolean isStarted() {
         return attributes != DECL_NOT_STARTED;
     }

     private List<Attribute.Compound> getPlaceholders() {
         List<Attribute.Compound> res = List.<Attribute.Compound>nil();
         for (Attribute.Compound a : filterDeclSentinels(attributes)) {
             if (a instanceof Placeholder) {
                 res = res.prepend(a);
             }
         }
         return res.reverse();
     }

     private List<Attribute.TypeCompound> getTypePlaceholders() {
         List<Attribute.TypeCompound> res = List.<Attribute.TypeCompound>nil();
         for (Attribute.TypeCompound a : type_attributes) {
             if (a instanceof Placeholder) {
                 res = res.prepend(a);
             }
         }
         return res.reverse();
     }

     /*
      * Replace Placeholders for repeating annotations with their containers
      */
     private <T extends Attribute.Compound> void complete(Annotate.AnnotateRepeatedContext<T> ctx) {
         Log log = ctx.log;
         Env<AttrContext> env = ctx.env;
         JavaFileObject oldSource = log.useSource(env.toplevel.sourcefile);
         try {
             // TODO: can we reduce duplication in the following branches?
             if (ctx.isTypeCompound) {
                 Assert.check(!isTypesEmpty());

                 if (isTypesEmpty()) {
                     return;
                 }

                 List<Attribute.TypeCompound> result = List.nil();
                 for (Attribute.TypeCompound a : getTypeAttributes()) {
                     if (a instanceof Placeholder) {
                         @SuppressWarnings("unchecked")
                         Placeholder<Attribute.TypeCompound> ph = (Placeholder<Attribute.TypeCompound>) a;
                         Attribute.TypeCompound replacement = replaceOne(ph, ph.getRepeatedContext());

                         if (null != replacement) {
                             result = result.prepend(replacement);
                         }
                     } else {
                         result = result.prepend(a);
                     }
                 }

                 type_attributes = result.reverse();

                 Assert.check(SymbolMetadata.this.getTypePlaceholders().isEmpty());
             } else {
                 Assert.check(!pendingCompletion());

                 if (isEmpty()) {
                     return;
                 }

                 List<Attribute.Compound> result = List.nil();
                 for (Attribute.Compound a : getDeclarationAttributes()) {
                     if (a instanceof Placeholder) {
                         @SuppressWarnings("unchecked")
                         Attribute.Compound replacement = replaceOne((Placeholder<T>) a, ctx);

                         if (null != replacement) {
                             result = result.prepend(replacement);
                         }
                     } else {
                         result = result.prepend(a);
                     }
                 }

                 attributes = result.reverse();

                 Assert.check(SymbolMetadata.this.getPlaceholders().isEmpty());
             }
         } finally {
             log.useSource(oldSource);
         }
     }

     private <T extends Attribute.Compound> T replaceOne(Placeholder<T> placeholder, Annotate.AnnotateRepeatedContext<T> ctx) {
         Log log = ctx.log;

         // Process repeated annotations
         T validRepeated = ctx.processRepeatedAnnotations(placeholder.getPlaceholderFor(), sym);

         if (validRepeated != null) {
             // Check that the container isn't manually
             // present along with repeated instances of
             // its contained annotation.
             ListBuffer<T> manualContainer = ctx.annotated.get(validRepeated.type.tsym);
             if (manualContainer != null) {
                 log.error(ctx.pos.get(manualContainer.first()), "invalid.repeatable.annotation.repeated.and.container.present",
                         manualContainer.first().type.tsym);
             }
         }

         // A null return will delete the Placeholder
         return validRepeated;
     }

     private static class Placeholder<T extends Attribute.Compound> extends Attribute.TypeCompound {

         private final Annotate.AnnotateRepeatedContext<T> ctx;
         private final List<T> placeholderFor;
         private final Symbol on;

         public Placeholder(Annotate.AnnotateRepeatedContext<T> ctx, List<T> placeholderFor, Symbol on) {
             super(on.type, List.<Pair<Symbol.MethodSymbol, Attribute>>nil(),
                     ctx.isTypeCompound ?
                             ((Attribute.TypeCompound)placeholderFor.head).position :
                                 new TypeAnnotationPosition());
             this.ctx = ctx;
             this.placeholderFor = placeholderFor;
             this.on = on;
         }

         @Override
         public String toString() {
             return "<placeholder: " + placeholderFor + " on: " + on + ">";
         }

         public List<T> getPlaceholderFor() {
             return placeholderFor;
         }

         public Annotate.AnnotateRepeatedContext<T> getRepeatedContext() {
             return ctx;
         }
     }
 }
	/*
	* Copyright (c) 2012, 2013, 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 java.util.Map;

	import javax.tools.JavaFileObject;

	import com.sun.tools.javac.comp.Annotate;
	import com.sun.tools.javac.comp.AttrContext;
	import com.sun.tools.javac.comp.Env;
	import com.sun.tools.javac.util.*;
	import com.sun.tools.javac.util.Assert;
	import com.sun.tools.javac.util.List;
	import com.sun.tools.javac.util.Log;
	import com.sun.tools.javac.util.Pair;
	import static com.sun.tools.javac.code.Kinds.PCK;

	/**
	* Container for all annotations (attributes in javac) on a Symbol.
	*
	* This class is explicitly mutable. Its contents will change when attributes
	* are annotated onto the Symbol. However this class depends on the facts that
	* List (in javac) is immutable.
	*
	* An instance of this class can be in one of three states:
	*
	* NOT_STARTED indicates that the Symbol this instance belongs to has not been
	* annotated (yet). Specifically if the declaration is not annotated this
	* instance will never move past NOT_STARTED. You can never go back to
	* NOT_STARTED.
	*
	* IN_PROGRESS annotations have been found on the declaration. Will be processed
	* later. You can reset to IN_PROGRESS. While IN_PROGRESS you can set the list
	* of attributes (and this moves out of the IN_PROGRESS state).
	*
	* "unnamed" this SymbolMetadata contains some attributes, possibly the final set.
	* While in this state you can only prepend or append to the attributes not set
	* it directly. You can also move back to the IN_PROGRESS state using reset().
	*
	* <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 class SymbolMetadata {

	private static final List<Attribute.Compound> DECL_NOT_STARTED = List.of(null);
	private static final List<Attribute.Compound> DECL_IN_PROGRESS = List.of(null);

	/*
	* This field should never be null
	*/
	private List<Attribute.Compound> attributes = DECL_NOT_STARTED;

	/*
	* Type attributes for this symbol.
	* This field should never be null.
	*/
	private List<Attribute.TypeCompound> type_attributes = List.<Attribute.TypeCompound>nil();

	/*
	* Type attributes of initializers in this class.
	* Unused if the current symbol is not a ClassSymbol.
	*/
	private List<Attribute.TypeCompound> init_type_attributes = List.<Attribute.TypeCompound>nil();

	/*
	* Type attributes of class initializers in this class.
	* Unused if the current symbol is not a ClassSymbol.
	*/
	private List<Attribute.TypeCompound> clinit_type_attributes = List.<Attribute.TypeCompound>nil();

	/*
	* The Symbol this SymbolMetadata instance belongs to
	*/
	private final Symbol sym;

	public SymbolMetadata(Symbol sym) {
	this.sym = sym;
	}

	public List<Attribute.Compound> getDeclarationAttributes() {
	return filterDeclSentinels(attributes);
	}

	public List<Attribute.TypeCompound> getTypeAttributes() {
	return type_attributes;
	}

	public List<Attribute.TypeCompound> getInitTypeAttributes() {
	return init_type_attributes;
	}

	public List<Attribute.TypeCompound> getClassInitTypeAttributes() {
	return clinit_type_attributes;
	}

	public void setDeclarationAttributes(List<Attribute.Compound> a) {
	Assert.check(pendingCompletion() \|\| !isStarted());
	if (a == null) {
	throw new NullPointerException();
	}
	attributes = a;
	}

	public void setTypeAttributes(List<Attribute.TypeCompound> a) {
	if (a == null) {
	throw new NullPointerException();
	}
	type_attributes = a;
	}

	public void setInitTypeAttributes(List<Attribute.TypeCompound> a) {
	if (a == null) {
	throw new NullPointerException();
	}
	init_type_attributes = a;
	}

	public void setClassInitTypeAttributes(List<Attribute.TypeCompound> a) {
	if (a == null) {
	throw new NullPointerException();
	}
	clinit_type_attributes = a;
	}

	public void setAttributes(SymbolMetadata other) {
	if (other == null) {
	throw new NullPointerException();
	}
	setDeclarationAttributes(other.getDeclarationAttributes());
	setTypeAttributes(other.getTypeAttributes());
	setInitTypeAttributes(other.getInitTypeAttributes());
	setClassInitTypeAttributes(other.getClassInitTypeAttributes());
	}

	public void setDeclarationAttributesWithCompletion(final Annotate.AnnotateRepeatedContext<Attribute.Compound> ctx) {
	Assert.check(pendingCompletion() \|\| (!isStarted() && sym.kind == PCK));
	this.setDeclarationAttributes(getAttributesForCompletion(ctx));
	}

	public void appendTypeAttributesWithCompletion(final Annotate.AnnotateRepeatedContext<Attribute.TypeCompound> ctx) {
	this.appendUniqueTypes(getAttributesForCompletion(ctx));
	}

	private <T extends Attribute.Compound> List<T> getAttributesForCompletion(
	final Annotate.AnnotateRepeatedContext<T> ctx) {

	Map<Symbol.TypeSymbol, ListBuffer<T>> annotated = ctx.annotated;
	boolean atLeastOneRepeated = false;
	List<T> buf = List.<T>nil();
	for (ListBuffer<T> lb : annotated.values()) {
	if (lb.size() == 1) {
	buf = buf.prepend(lb.first());
	} else { // repeated
	// This will break when other subtypes of Attributs.Compound
	// are introduced, because PlaceHolder is a subtype of TypeCompound.
	T res;
	@SuppressWarnings("unchecked")
	T ph = (T) new Placeholder<>(ctx, lb.toList(), sym);
	res = ph;
	buf = buf.prepend(res);
	atLeastOneRepeated = true;
	}
	}

	if (atLeastOneRepeated) {
	// The Symbol s is now annotated with a combination of
	// finished non-repeating annotations and placeholders for
	// repeating annotations.
	//
	// We need to do this in two passes because when creating
	// a container for a repeating annotation we must
	// guarantee that the @Repeatable on the
	// contained annotation is fully annotated
	//
	// The way we force this order is to do all repeating
	// annotations in a pass after all non-repeating are
	// finished. This will work because @Repeatable
	// is non-repeating and therefore will be annotated in the
	// fist pass.

	// Queue a pass that will replace Attribute.Placeholders
	// with Attribute.Compound (made from synthesized containers).
	ctx.annotateRepeated(new Annotate.Worker() {
	@Override
	public String toString() {
	return "repeated annotation pass of: " + sym + " in: " + sym.owner;
	}

	@Override
	public void run() {
	complete(ctx);
	}
	});
	}
	// Add non-repeating attributes
	return buf.reverse();
	}

	public SymbolMetadata reset() {
	attributes = DECL_IN_PROGRESS;
	return this;
	}

	public boolean isEmpty() {
	return !isStarted()
	\|\| pendingCompletion()
	\|\| attributes.isEmpty();
	}

	public boolean isTypesEmpty() {
	return type_attributes.isEmpty();
	}

	public boolean pendingCompletion() {
	return attributes == DECL_IN_PROGRESS;
	}

	public SymbolMetadata append(List<Attribute.Compound> l) {
	attributes = filterDeclSentinels(attributes);

	if (l.isEmpty()) {
	// no-op
	} else if (attributes.isEmpty()) {
	attributes = l;
	} else {
	attributes = attributes.appendList(l);
	}
	return this;
	}

	public SymbolMetadata appendUniqueTypes(List<Attribute.TypeCompound> l) {
	if (l.isEmpty()) {
	// no-op
	} else if (type_attributes.isEmpty()) {
	type_attributes = l;
	} else {
	// TODO: in case we expect a large number of annotations, this
	// might be inefficient.
	for (Attribute.TypeCompound tc : l) {
	if (!type_attributes.contains(tc))
	type_attributes = type_attributes.append(tc);
	}
	}
	return this;
	}

	public SymbolMetadata appendInitTypeAttributes(List<Attribute.TypeCompound> l) {
	if (l.isEmpty()) {
	// no-op
	} else if (init_type_attributes.isEmpty()) {
	init_type_attributes = l;
	} else {
	init_type_attributes = init_type_attributes.appendList(l);
	}
	return this;
	}

	public SymbolMetadata appendClassInitTypeAttributes(List<Attribute.TypeCompound> l) {
	if (l.isEmpty()) {
	// no-op
	} else if (clinit_type_attributes.isEmpty()) {
	clinit_type_attributes = l;
	} else {
	clinit_type_attributes = clinit_type_attributes.appendList(l);
	}
	return this;
	}

	public SymbolMetadata prepend(List<Attribute.Compound> l) {
	attributes = filterDeclSentinels(attributes);

	if (l.isEmpty()) {
	// no-op
	} else if (attributes.isEmpty()) {
	attributes = l;
	} else {
	attributes = attributes.prependList(l);
	}
	return this;
	}

	private List<Attribute.Compound> filterDeclSentinels(List<Attribute.Compound> a) {
	return (a == DECL_IN_PROGRESS \|\| a == DECL_NOT_STARTED)
	? List.<Attribute.Compound>nil()
	: a;
	}

	private boolean isStarted() {
	return attributes != DECL_NOT_STARTED;
	}

	private List<Attribute.Compound> getPlaceholders() {
	List<Attribute.Compound> res = List.<Attribute.Compound>nil();
	for (Attribute.Compound a : filterDeclSentinels(attributes)) {
	if (a instanceof Placeholder) {
	res = res.prepend(a);
	}
	}
	return res.reverse();
	}

	private List<Attribute.TypeCompound> getTypePlaceholders() {
	List<Attribute.TypeCompound> res = List.<Attribute.TypeCompound>nil();
	for (Attribute.TypeCompound a : type_attributes) {
	if (a instanceof Placeholder) {
	res = res.prepend(a);
	}
	}
	return res.reverse();
	}

	/*
	* Replace Placeholders for repeating annotations with their containers
	*/
	private <T extends Attribute.Compound> void complete(Annotate.AnnotateRepeatedContext<T> ctx) {
	Log log = ctx.log;
	Env<AttrContext> env = ctx.env;
	JavaFileObject oldSource = log.useSource(env.toplevel.sourcefile);
	try {
	// TODO: can we reduce duplication in the following branches?
	if (ctx.isTypeCompound) {
	Assert.check(!isTypesEmpty());

	if (isTypesEmpty()) {
	return;
	}

	List<Attribute.TypeCompound> result = List.nil();
	for (Attribute.TypeCompound a : getTypeAttributes()) {
	if (a instanceof Placeholder) {
	@SuppressWarnings("unchecked")
	Placeholder<Attribute.TypeCompound> ph = (Placeholder<Attribute.TypeCompound>) a;
	Attribute.TypeCompound replacement = replaceOne(ph, ph.getRepeatedContext());

	if (null != replacement) {
	result = result.prepend(replacement);
	}
	} else {
	result = result.prepend(a);
	}
	}

	type_attributes = result.reverse();

	Assert.check(SymbolMetadata.this.getTypePlaceholders().isEmpty());
	} else {
	Assert.check(!pendingCompletion());

	if (isEmpty()) {
	return;
	}

	List<Attribute.Compound> result = List.nil();
	for (Attribute.Compound a : getDeclarationAttributes()) {
	if (a instanceof Placeholder) {
	@SuppressWarnings("unchecked")
	Attribute.Compound replacement = replaceOne((Placeholder<T>) a, ctx);

	if (null != replacement) {
	result = result.prepend(replacement);
	}
	} else {
	result = result.prepend(a);
	}
	}

	attributes = result.reverse();

	Assert.check(SymbolMetadata.this.getPlaceholders().isEmpty());
	}
	} finally {
	log.useSource(oldSource);
	}
	}

	private <T extends Attribute.Compound> T replaceOne(Placeholder<T> placeholder, Annotate.AnnotateRepeatedContext<T> ctx) {
	Log log = ctx.log;

	// Process repeated annotations
	T validRepeated = ctx.processRepeatedAnnotations(placeholder.getPlaceholderFor(), sym);

	if (validRepeated != null) {
	// Check that the container isn't manually
	// present along with repeated instances of
	// its contained annotation.
	ListBuffer<T> manualContainer = ctx.annotated.get(validRepeated.type.tsym);
	if (manualContainer != null) {
	log.error(ctx.pos.get(manualContainer.first()), "invalid.repeatable.annotation.repeated.and.container.present",
	manualContainer.first().type.tsym);
	}
	}

	// A null return will delete the Placeholder
	return validRepeated;
	}

	private static class Placeholder<T extends Attribute.Compound> extends Attribute.TypeCompound {

	private final Annotate.AnnotateRepeatedContext<T> ctx;
	private final List<T> placeholderFor;
	private final Symbol on;

	public Placeholder(Annotate.AnnotateRepeatedContext<T> ctx, List<T> placeholderFor, Symbol on) {
	super(on.type, List.<Pair<Symbol.MethodSymbol, Attribute>>nil(),
	ctx.isTypeCompound ?
	((Attribute.TypeCompound)placeholderFor.head).position :
	new TypeAnnotationPosition());
	this.ctx = ctx;
	this.placeholderFor = placeholderFor;
	this.on = on;
	}

	@Override
	public String toString() {
	return "<placeholder: " + placeholderFor + " on: " + on + ">";
	}

	public List<T> getPlaceholderFor() {
	return placeholderFor;
	}

	public Annotate.AnnotateRepeatedContext<T> getRepeatedContext() {
	return ctx;
	}
	}
	}