/**
* Return a conservative estimage on the min/max number of items of a type.
*
* @return {@code maxCount << 12 | minCount & 0xFFF}, where a {@code maxCount} of -1 means
* unbounded.
*/
public static int itemCountRange(Type type) {
if (type instanceof SingletonType) return (1 << 12) | 1;
if (type instanceof OccurrenceType) {
OccurrenceType occ = (OccurrenceType) type;
int min = occ.minOccurs();
int max = occ.maxOccurs();
int bnum = itemCountRange(occ.getBase());
if ((min == 1 && max == 1) || bnum == 0) return bnum;
if (max > 0xfffff) max = -1;
if (max == 0) return 0;
int bmin = bnum & 0xfff;
int bmax = bnum >> 12;
if (bnum != 0x1001) {
if (min > 0xfff) min = 0xfff;
min = min * bmin;
if (min > 0xfff) min = 0xfff;
if (max < 0 || bmax < 0) max = -1;
else max = max * bmax;
if (max > 0xfffff) max = -1;
}
return (max << 12) | min;
}
if (type instanceof PrimType) return type.isVoid() ? 0 : 0x1001;
if (type instanceof ArrayType) return 0x1001;
if (type instanceof ObjectType) {
int cmp = type.compare(Compilation.typeValues);
if (cmp == -3) return 0x1001;
}
return -1 << 12;
}
public int compare(Type other) {
if (other instanceof OccurrenceType) {
OccurrenceType occOther = (OccurrenceType) other;
if (minOccurs == occOther.minOccurs && maxOccurs == occOther.maxOccurs)
return base.compare(occOther.getBase());
}
/*
Type primeThis = itemPrimeType(getBase());
Type primeOther = itemPrimeType(other);
FIXME: Compare primThis with primOther AND the occurrence numbers.
*/
return -2;
}
/** A type that matches some number of repetitions of a basetype. */
public class OccurrenceType extends ObjectType implements Externalizable, TypeValue {
Type base;
int minOccurs;
int maxOccurs;
public Type getBase() {
return base;
}
public int minOccurs() {
return minOccurs;
}
public int maxOccurs() {
return maxOccurs;
}
public OccurrenceType(Type base, int minOccurs, int maxOccurs) {
this.base = base;
this.minOccurs = minOccurs;
this.maxOccurs = maxOccurs;
}
public static Type getInstance(Type base, int minOccurs, int maxOccurs) {
if (minOccurs == 1 && maxOccurs == 1) return base;
if (minOccurs == 0
&& maxOccurs < 0
&& (base == SingletonType.instance || base == Type.pointer_type)) return Type.pointer_type;
return new OccurrenceType(base, minOccurs, maxOccurs);
}
public static final Type emptySequenceType =
OccurrenceType.getInstance(SingletonType.instance, 0, 0);
public Type getImplementationType() {
return Type.pointer_type;
}
public int compare(Type other) {
if (other instanceof OccurrenceType) {
OccurrenceType occOther = (OccurrenceType) other;
if (minOccurs == occOther.minOccurs && maxOccurs == occOther.maxOccurs)
return base.compare(occOther.getBase());
}
/*
Type primeThis = itemPrimeType(getBase());
Type primeOther = itemPrimeType(other);
FIXME: Compare primThis with primOther AND the occurrence numbers.
*/
return -2;
}
public Object coerceFromObject(Object obj) {
if (obj instanceof Values) {
} else {
// Assumes that base is an item type. FIXME.
if (minOccurs <= 1 && maxOccurs != 0) return base.coerceFromObject(obj);
}
// FIXME
if (!isInstance(obj)) throw new ClassCastException();
return obj;
}
public boolean isInstance(Object obj) {
if (obj instanceof Values) {
Values vals = (Values) obj;
int pos = vals.startPos();
int n = 0;
if (base instanceof ItemPredicate) {
ItemPredicate pred = (ItemPredicate) base;
for (; ; ) {
boolean matches;
matches = pred.isInstancePos(vals, pos);
pos = vals.nextPos(pos);
if (pos == 0) {
return n >= minOccurs && (maxOccurs < 0 || n <= maxOccurs);
}
if (!matches) return false;
n++;
}
} else {
for (; ; ) {
pos = vals.nextPos(pos);
if (pos == 0) {
return n >= minOccurs && (maxOccurs < 0 || n <= maxOccurs);
}
Object value = vals.getPosPrevious(pos);
if (!base.isInstance(value)) return false;
n++;
}
}
} else {
if (minOccurs > 1 || maxOccurs == 0) return false;
return base.isInstance(obj);
}
}
public void emitTestIf(Variable incoming, Declaration decl, Compilation comp) {
CodeAttr code = comp.getCode();
if (incoming != null) code.emitLoad(incoming);
if (decl != null) {
code.emitDup();
decl.compileStore(comp);
}
comp.compileConstant(this);
code.emitSwap();
code.emitInvokeVirtual(isInstanceMethod);
code.emitIfIntNotZero();
}
public void emitIsInstance(Variable incoming, Compilation comp, Target target) {
gnu.kawa.reflect.InstanceOf.emitIsInstance(this, incoming, comp, target);
}
public Expression convertValue(Expression value) {
return null;
}
public Procedure getConstructor() {
return null;
}
/**
* Return a conservative estimage on the min/max number of items of a type.
*
* @return {@code maxCount << 12 | minCount & 0xFFF}, where a {@code maxCount} of -1 means
* unbounded.
*/
public static int itemCountRange(Type type) {
if (type instanceof SingletonType) return (1 << 12) | 1;
if (type instanceof OccurrenceType) {
OccurrenceType occ = (OccurrenceType) type;
int min = occ.minOccurs();
int max = occ.maxOccurs();
int bnum = itemCountRange(occ.getBase());
if ((min == 1 && max == 1) || bnum == 0) return bnum;
if (max > 0xfffff) max = -1;
if (max == 0) return 0;
int bmin = bnum & 0xfff;
int bmax = bnum >> 12;
if (bnum != 0x1001) {
if (min > 0xfff) min = 0xfff;
min = min * bmin;
if (min > 0xfff) min = 0xfff;
if (max < 0 || bmax < 0) max = -1;
else max = max * bmax;
if (max > 0xfffff) max = -1;
}
return (max << 12) | min;
}
if (type instanceof PrimType) return type.isVoid() ? 0 : 0x1001;
if (type instanceof ArrayType) return 0x1001;
if (type instanceof ObjectType) {
int cmp = type.compare(Compilation.typeValues);
if (cmp == -3) return 0x1001;
}
return -1 << 12;
}
/**
* Returna a quantifer kind for a sequence type.
*
* @return '0' if type is known to be a void (0-item) type; '1' if type is known to be a
* single-item type; '?' if type matches a sequence of 0 or 1 items; '+' if type matches a
* sequence of 1 or more items; '*' otherwise.
*/
public static char itemCountCode(Type type) {
int num = itemCountRange(type);
int min = num & 0xFFF;
int max = num >> 12;
return max == 0 ? '0' : min == 0 ? (max == 1 ? '?' : '*') : min == 1 && max == 1 ? '1' : '+';
}
public static boolean itemCountIsZeroOrOne(Type type) {
// cute hack for: max == 0 || max == 1.
return (itemCountRange(type) >> 13) == 0;
}
public static boolean itemCountIsOne(Type type) {
return itemCountRange(type) == 0x1001;
}
/** QUery formal semantics "prime type" */
public static Type itemPrimeType(Type type) {
while (type instanceof OccurrenceType) type = ((OccurrenceType) type).getBase();
return itemCountIsOne(type) ? type : SingletonType.instance;
}
public void writeExternal(ObjectOutput out) throws IOException {
out.writeObject(base);
out.writeInt(minOccurs);
out.writeInt(maxOccurs);
}
public String toString() {
String b = base.toString();
boolean parens = b == null || b.indexOf(' ') >= 0;
StringBuffer sbuf = new StringBuffer();
if (parens) sbuf.append('(');
sbuf.append(b);
if (parens) sbuf.append(')');
if (minOccurs == 1 && maxOccurs == 1) ;
else if (minOccurs == 0 && maxOccurs == 1) sbuf.append('?');
else if (minOccurs == 1 && maxOccurs == -1) sbuf.append('+');
else if (minOccurs == 0 && maxOccurs == -1) sbuf.append('*');
else {
sbuf.append('{');
sbuf.append(minOccurs);
sbuf.append(',');
if (maxOccurs >= 0) sbuf.append(maxOccurs);
else sbuf.append('*');
sbuf.append('}');
}
return sbuf.toString();
}
public void readExternal(ObjectInput in) throws IOException, ClassNotFoundException {
base = (Type) in.readObject();
minOccurs = in.readInt();
maxOccurs = in.readInt();
}
public static final ClassType typeOccurrenceType =
ClassType.make("gnu.kawa.reflect.OccurrenceType");
static final Method isInstanceMethod = typeOccurrenceType.getDeclaredMethod("isInstance", 1);
}
