7151010: Add compiler support for repeating annotations
Reviewed-by: jjg, mcimadamore
/*
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* DO NOT ALTER OR REMOVE COPYRIGHT NOTICES OR THIS FILE HEADER.
*
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*
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* 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.
*
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package com.sun.tools.javac.comp;
import java.util.Map;
import java.util.Objects;
import com.sun.tools.javac.util.*;
import com.sun.tools.javac.util.JCDiagnostic.DiagnosticPosition;
import com.sun.tools.javac.code.*;
import com.sun.tools.javac.code.Symbol.*;
import com.sun.tools.javac.tree.*;
import com.sun.tools.javac.tree.JCTree.*;
import static com.sun.tools.javac.tree.JCTree.Tag.*;
/** Enter annotations on symbols. Annotations accumulate in a queue,
* which is processed at the top level of any set of recursive calls
* requesting it be processed.
*
* <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 Annotate {
protected static final Context.Key<Annotate> annotateKey =
new Context.Key<Annotate>();
public static Annotate instance(Context context) {
Annotate instance = context.get(annotateKey);
if (instance == null)
instance = new Annotate(context);
return instance;
}
final Attr attr;
final TreeMaker make;
final Log log;
final Symtab syms;
final Names names;
final Resolve rs;
final Types types;
final ConstFold cfolder;
final Check chk;
protected Annotate(Context context) {
context.put(annotateKey, this);
attr = Attr.instance(context);
make = TreeMaker.instance(context);
log = Log.instance(context);
syms = Symtab.instance(context);
names = Names.instance(context);
rs = Resolve.instance(context);
types = Types.instance(context);
cfolder = ConstFold.instance(context);
chk = Check.instance(context);
}
/* ********************************************************************
* Queue maintenance
*********************************************************************/
private int enterCount = 0;
ListBuffer<Annotator> q = new ListBuffer<Annotator>();
ListBuffer<Annotator> repeatedQ = new ListBuffer<Annotator>();
public void normal(Annotator a) {
q.append(a);
}
public void earlier(Annotator a) {
q.prepend(a);
}
public void repeated(Annotator a) {
repeatedQ.append(a);
}
/** Called when the Enter phase starts. */
public void enterStart() {
enterCount++;
}
/** Called after the Enter phase completes. */
public void enterDone() {
enterCount--;
flush();
}
public void flush() {
if (enterCount != 0) return;
enterCount++;
try {
while (q.nonEmpty())
q.next().enterAnnotation();
while (repeatedQ.nonEmpty()) {
repeatedQ.next().enterAnnotation();
}
} finally {
enterCount--;
}
}
/** A client that has annotations to add registers an annotator,
* the method it will use to add the annotation. There are no
* parameters; any needed data should be captured by the
* Annotator.
*/
public interface Annotator {
void enterAnnotation();
String toString();
}
/**
* This context contains all the information needed to synthesize new
* annotations trees by the completer for repeating annotations.
*/
public class AnnotateRepeatedContext {
public final Env<AttrContext> env;
public final Map<Symbol.TypeSymbol, ListBuffer<Attribute.Compound>> annotated;
public final Map<Attribute.Compound, JCDiagnostic.DiagnosticPosition> pos;
public final Log log;
public AnnotateRepeatedContext(Env<AttrContext> env,
Map<Symbol.TypeSymbol, ListBuffer<Attribute.Compound>> annotated,
Map<Attribute.Compound, JCDiagnostic.DiagnosticPosition> pos,
Log log) {
Objects.requireNonNull(env);
Objects.requireNonNull(annotated);
Objects.requireNonNull(pos);
Objects.requireNonNull(log);
this.env = env;
this.annotated = annotated;
this.pos = pos;
this.log = log;
}
/**
* Process a list of repeating annotations returning a new
* Attribute.Compound that is the attribute for the synthesized tree
* for the container.
*
* @param repeatingAnnotations a List of repeating annotations
* @return a new Attribute.Compound that is the container for the repeatingAnnotations
*/
public Attribute.Compound processRepeatedAnnotations(List<Attribute.Compound> repeatingAnnotations) {
return Annotate.this.processRepeatedAnnotations(repeatingAnnotations, this);
}
/**
* Queue the Annotator a on the repeating annotations queue of the
* Annotate instance this context belongs to.
*
* @param a the Annotator to enqueue for repeating annotation annotating
*/
public void annotateRepeated(Annotator a) {
Annotate.this.repeated(a);
}
}
/* ********************************************************************
* Compute an attribute from its annotation.
*********************************************************************/
/** Process a single compound annotation, returning its
* Attribute. Used from MemberEnter for attaching the attributes
* to the annotated symbol.
*/
Attribute.Compound enterAnnotation(JCAnnotation a,
Type expected,
Env<AttrContext> env) {
// The annotation might have had its type attributed (but not checked)
// by attr.attribAnnotationTypes during MemberEnter, in which case we do not
// need to do it again.
Type at = (a.annotationType.type != null ? a.annotationType.type
: attr.attribType(a.annotationType, env));
a.type = chk.checkType(a.annotationType.pos(), at, expected);
if (a.type.isErroneous())
return new Attribute.Compound(a.type, List.<Pair<MethodSymbol,Attribute>>nil());
if ((a.type.tsym.flags() & Flags.ANNOTATION) == 0) {
log.error(a.annotationType.pos(),
"not.annotation.type", a.type.toString());
return new Attribute.Compound(a.type, List.<Pair<MethodSymbol,Attribute>>nil());
}
List<JCExpression> args = a.args;
if (args.length() == 1 && !args.head.hasTag(ASSIGN)) {
// special case: elided "value=" assumed
args.head = make.at(args.head.pos).
Assign(make.Ident(names.value), args.head);
}
ListBuffer<Pair<MethodSymbol,Attribute>> buf =
new ListBuffer<Pair<MethodSymbol,Attribute>>();
for (List<JCExpression> tl = args; tl.nonEmpty(); tl = tl.tail) {
JCExpression t = tl.head;
if (!t.hasTag(ASSIGN)) {
log.error(t.pos(), "annotation.value.must.be.name.value");
continue;
}
JCAssign assign = (JCAssign)t;
if (!assign.lhs.hasTag(IDENT)) {
log.error(t.pos(), "annotation.value.must.be.name.value");
continue;
}
JCIdent left = (JCIdent)assign.lhs;
Symbol method = rs.resolveQualifiedMethod(left.pos(),
env,
a.type,
left.name,
List.<Type>nil(),
null);
left.sym = method;
left.type = method.type;
if (method.owner != a.type.tsym)
log.error(left.pos(), "no.annotation.member", left.name, a.type);
Type result = method.type.getReturnType();
Attribute value = enterAttributeValue(result, assign.rhs, env);
if (!method.type.isErroneous())
buf.append(new Pair<MethodSymbol,Attribute>
((MethodSymbol)method, value));
t.type = result;
}
return new Attribute.Compound(a.type, buf.toList());
}
Attribute enterAttributeValue(Type expected,
JCExpression tree,
Env<AttrContext> env) {
//first, try completing the attribution value sym - if a completion
//error is thrown, we should recover gracefully, and display an
//ordinary resolution diagnostic.
try {
expected.tsym.complete();
} catch(CompletionFailure e) {
log.error(tree.pos(), "cant.resolve", Kinds.kindName(e.sym), e.sym);
return new Attribute.Error(expected);
}
if (expected.isPrimitive() || types.isSameType(expected, syms.stringType)) {
Type result = attr.attribExpr(tree, env, expected);
if (result.isErroneous())
return new Attribute.Error(expected);
if (result.constValue() == null) {
log.error(tree.pos(), "attribute.value.must.be.constant");
return new Attribute.Error(expected);
}
result = cfolder.coerce(result, expected);
return new Attribute.Constant(expected, result.constValue());
}
if (expected.tsym == syms.classType.tsym) {
Type result = attr.attribExpr(tree, env, expected);
if (result.isErroneous())
return new Attribute.Error(expected);
if (TreeInfo.name(tree) != names._class) {
log.error(tree.pos(), "annotation.value.must.be.class.literal");
return new Attribute.Error(expected);
}
return new Attribute.Class(types,
(((JCFieldAccess) tree).selected).type);
}
if ((expected.tsym.flags() & Flags.ANNOTATION) != 0) {
if (!tree.hasTag(ANNOTATION)) {
log.error(tree.pos(), "annotation.value.must.be.annotation");
expected = syms.errorType;
}
return enterAnnotation((JCAnnotation)tree, expected, env);
}
if (expected.tag == TypeTags.ARRAY) { // should really be isArray()
if (!tree.hasTag(NEWARRAY)) {
tree = make.at(tree.pos).
NewArray(null, List.<JCExpression>nil(), List.of(tree));
}
JCNewArray na = (JCNewArray)tree;
if (na.elemtype != null) {
log.error(na.elemtype.pos(), "new.not.allowed.in.annotation");
return new Attribute.Error(expected);
}
ListBuffer<Attribute> buf = new ListBuffer<Attribute>();
for (List<JCExpression> l = na.elems; l.nonEmpty(); l=l.tail) {
buf.append(enterAttributeValue(types.elemtype(expected),
l.head,
env));
}
na.type = expected;
return new Attribute.
Array(expected, buf.toArray(new Attribute[buf.length()]));
}
if (expected.tag == TypeTags.CLASS &&
(expected.tsym.flags() & Flags.ENUM) != 0) {
attr.attribExpr(tree, env, expected);
Symbol sym = TreeInfo.symbol(tree);
if (sym == null ||
TreeInfo.nonstaticSelect(tree) ||
sym.kind != Kinds.VAR ||
(sym.flags() & Flags.ENUM) == 0) {
log.error(tree.pos(), "enum.annotation.must.be.enum.constant");
return new Attribute.Error(expected);
}
VarSymbol enumerator = (VarSymbol) sym;
return new Attribute.Enum(expected, enumerator);
}
if (!expected.isErroneous())
log.error(tree.pos(), "annotation.value.not.allowable.type");
return new Attribute.Error(attr.attribExpr(tree, env, expected));
}
/* *********************************
* Support for repeating annotations
***********************************/
/* Process repeated annotations. This method returns the
* synthesized container annotation or null IFF all repeating
* annotation are invalid. This method reports errors/warnings.
*/
private Attribute.Compound processRepeatedAnnotations(List<Attribute.Compound> annotations,
AnnotateRepeatedContext ctx) {
Attribute.Compound firstOccurrence = annotations.head;
List<Attribute> repeated = List.nil();
Type origAnnoType;
Type arrayOfOrigAnnoType = null;
Type targetContainerType = null;
MethodSymbol containerValueSymbol = null;
Assert.check(!annotations.isEmpty() &&
!annotations.tail.isEmpty()); // i.e. size() > 1
for (List<Attribute.Compound> al = annotations;
!al.isEmpty();
al = al.tail)
{
Attribute.Compound currentAnno = al.head;
origAnnoType = currentAnno.type;
if (arrayOfOrigAnnoType == null) {
arrayOfOrigAnnoType = types.makeArrayType(origAnnoType);
}
Type currentContainerType = getContainingType(currentAnno, ctx.pos.get(currentAnno));
if (currentContainerType == null) {
continue;
}
// Assert that the target Container is == for all repeated
// annos of the same annotation type, the types should
// come from the same Symbol, i.e. be '=='
Assert.check(targetContainerType == null || currentContainerType == targetContainerType);
targetContainerType = currentContainerType;
containerValueSymbol = validateContainer(targetContainerType, origAnnoType, ctx.pos.get(currentAnno));
if (containerValueSymbol == null) { // Check of CA type failed
// errors are already reported
continue;
}
repeated = repeated.prepend(currentAnno);
}
if (!repeated.isEmpty()) {
repeated = repeated.reverse();
JCAnnotation annoTree;
TreeMaker m = make.at(ctx.pos.get(firstOccurrence));
Pair<MethodSymbol, Attribute> p =
new Pair<MethodSymbol, Attribute>(containerValueSymbol,
new Attribute.Array(arrayOfOrigAnnoType, repeated));
annoTree = m.Annotation(new Attribute.Compound(targetContainerType,
List.of(p)));
Attribute.Compound c = enterAnnotation(annoTree,
targetContainerType,
ctx.env);
return c;
} else {
return null; // errors should have been reported elsewhere
}
}
/** Fetches the actual Type that should be the containing annotation. */
private Type getContainingType(Attribute.Compound currentAnno,
DiagnosticPosition pos)
{
Type origAnnoType = currentAnno.type;
TypeSymbol origAnnoDecl = origAnnoType.tsym;
// Fetch the ContainedBy annotation from the current
// annotation's declaration, or null if it has none
Attribute.Compound ca = origAnnoDecl.attribute(syms.containedByType.tsym);
if (ca == null) { // has no ContainedBy annotation
log.error(pos, "duplicate.annotation.missing.container", origAnnoType);
return null;
}
return filterSame(extractContainingType(ca, pos, origAnnoDecl),
origAnnoType);
}
// returns null if t is same as 's', returns 't' otherwise
private Type filterSame(Type t, Type s) {
if (t == null || s == null) {
return t;
}
return types.isSameType(t, s) ? null : t;
}
/** Extract the actual Type to be used for a containing annotation. */
private Type extractContainingType(Attribute.Compound ca,
DiagnosticPosition pos,
TypeSymbol annoDecl)
{
// The next three checks check that the ContainedBy annotation
// on the declaration of the annotation type that is repeating is
// valid.
// ContainedBy must have at least one element
if (ca.values.isEmpty()) {
log.error(pos, "invalid.containedby.annotation", annoDecl);
return null;
}
Pair<MethodSymbol,Attribute> p = ca.values.head;
Name name = p.fst.name;
if (name != names.value) { // should contain only one element, named "value"
log.error(pos, "invalid.containedby.annotation", annoDecl);
return null;
}
if (!(p.snd instanceof Attribute.Class)) { // check that the value of "value" is an Attribute.Class
log.error(pos, "invalid.containedby.annotation", annoDecl);
return null;
}
return ((Attribute.Class)p.snd).getValue();
}
/* Validate that the suggested targetContainerType Type is a valid
* container type for repeated instances of originalAnnoType
* annotations. Return null and report errors if this is not the
* case, return the MethodSymbol of the value element in
* targetContainerType if it is suitable (this is needed to
* synthesize the container). */
private MethodSymbol validateContainer(Type targetContainerType,
Type originalAnnoType,
DiagnosticPosition pos) {
MethodSymbol containerValueSymbol = null;
boolean fatalError = false;
// Validate that there is a (and only 1) value method
Scope scope = targetContainerType.tsym.members();
int nr_value_elems = 0;
boolean error = false;
for(Symbol elm : scope.getElementsByName(names.value)) {
nr_value_elems++;
if (nr_value_elems == 1 &&
elm.kind == Kinds.MTH) {
containerValueSymbol = (MethodSymbol)elm;
} else {
error = true;
}
}
if (error) {
log.error(pos,
"invalid.containedby.annotation.multiple.values",
targetContainerType,
nr_value_elems);
return null;
} else if (nr_value_elems == 0) {
log.error(pos,
"invalid.containedby.annotation.no.value",
targetContainerType);
return null;
}
// validate that the 'value' element is a method
// probably "impossible" to fail this
if (containerValueSymbol.kind != Kinds.MTH) {
log.error(pos,
"invalid.containedby.annotation.invalid.value",
targetContainerType);
fatalError = true;
}
// validate that the 'value' element has the correct return type
// i.e. array of original anno
Type valueRetType = containerValueSymbol.type.getReturnType();
Type expectedType = types.makeArrayType(originalAnnoType);
if (!(types.isArray(valueRetType) &&
types.isSameType(expectedType, valueRetType))) {
log.error(pos,
"invalid.containedby.annotation.value.return",
targetContainerType,
valueRetType,
expectedType);
fatalError = true;
}
// validate that all other elements of containing type has defaults
scope = targetContainerType.tsym.members();
error = false;
for(Symbol elm : scope.getElements()) {
if (elm.name != names.value &&
elm.kind == Kinds.MTH &&
((MethodSymbol)elm).defaultValue == null) {
log.error(pos,
"invalid.containedby.annotation.elem.nondefault",
targetContainerType,
elm);
containerValueSymbol = null;
error = true;
}
}
if (error) {
fatalError = true;
}
// Explicitly no check for/validity of @ContainerFor. That is
// done on declaration of the container, and at reflect time.
// The rest of the conditions for a valid containing annotation are made
// in Check.validateRepeatedAnnotaton();
return fatalError ? null : containerValueSymbol;
}
}