Add support of annotation fields and default values

teavm-classlib/src/main/java/org/teavm/classlib/java/lang/TClass.java

@@ -237,7 +237,7 @@ public class TClass<T> extends TObject implements TAnnotatedElement {
         }
         annotationsByType = new HashMap<>();
         for (TAnnotation annot : getAnnotations()) {
-            annotationsByType.put((TClass<?>)(Object)annot.getClass(), annot);
+            annotationsByType.put((TClass<?>)(Object)annot.annotationType(), annot);
         }
     }
 }

teavm-classlib/src/main/java/org/teavm/classlib/java/lang/annotation/TAnnotation.java

@@ -15,9 +15,13 @@
  */
 package org.teavm.classlib.java.lang.annotation;
 
+import org.teavm.javascript.spi.Rename;
+
 /**
  *
  * @author Alexey Andreev
  */
 public @interface TAnnotation {
+    @Rename("annotationType")
+    Class<?> annotationType0();
 }

teavm-classlib/src/main/java/org/teavm/classlib/java/lang/reflect/AnnotationClassTransformer.java

@@ -85,9 +85,11 @@ public class AnnotationClassTransformer implements ClassHolderTransformer {
         List<ValueEmitter> params = new ArrayList<>();
         for (MethodReader methodDecl : annotationClass.getMethods()) {
             ctorSignature.add(methodDecl.getResultType());
-            AnnotationValue value = annotation.getValue(className);
-            params.add(value != null ? generateAnnotationValue(classSource, pe, methodDecl.getResultType(), value) :
-                    pe.constantNull());
+            AnnotationValue value = annotation.getValue(methodDecl.getName());
+            if (value == null) {
+                value = methodDecl.getAnnotationDefault();
+            }
+            params.add(generateAnnotationValue(classSource, pe, methodDecl.getResultType(), value));
         }
         ctorSignature.add(ValueType.VOID);
 

teavm-classlib/src/main/java/org/teavm/classlib/java/lang/reflect/AnnotationDependencyListener.java

@@ -122,6 +122,12 @@ public class AnnotationDependencyListener implements DependencyListener {
         pe.exit();
         implementor.addMethod(ctor);
 
+        MethodHolder annotTypeMethod = new MethodHolder("annotationType", ValueType.parse(Class.class));
+        pe = ProgramEmitter.create(annotTypeMethod);
+        pe.wrapNew();
+        pe.constant(ValueType.object(annotationType)).returnValue();
+        implementor.addMethod(annotTypeMethod);
+
         return implementor;
     }
 

teavm-core/src/main/java/org/teavm/cache/DiskCachedClassHolderSource.java

@@ -239,12 +239,16 @@ public class DiskCachedClassHolderSource implements ClassHolderSource {
         }
     }
 
-    private void writeAnnotation(DataOutput output, AnnotationHolder annotation) throws IOException {
+    private void writeAnnotation(DataOutput output, AnnotationReader annotation) throws IOException {
         output.writeInt(symbolTable.lookup(annotation.getType()));
-        output.writeShort(annotation.getValues().size());
-        for (Map.Entry<String, AnnotationValue> entry : annotation.getValues().entrySet()) {
-            output.writeInt(symbolTable.lookup(entry.getKey()));
-            writeAnnotationValue(output, entry.getValue());
+        int fieldCount = 0;
+        for (@SuppressWarnings("unused") String field : annotation.getAvailableFields()) {
+            ++fieldCount;
+        }
+        output.writeShort(fieldCount);
+        for (String field : annotation.getAvailableFields()) {
+            output.writeInt(symbolTable.lookup(field));
+            writeAnnotationValue(output, annotation.getValue(field));
         }
     }
 

teavm-core/src/main/java/org/teavm/model/AnnotationValue.java

@@ -88,7 +88,7 @@ public class AnnotationValue {
         this.value = value;
     }
 
-    public AnnotationValue(AnnotationHolder value) {
+    public AnnotationValue(AnnotationReader value) {
         this.type = ANNOTATION;
         this.value = value;
     }
@@ -176,11 +176,11 @@ public class AnnotationValue {
         return (FieldReference)value;
     }
 
-    public AnnotationHolder getAnnotation() {
+    public AnnotationReader getAnnotation() {
         if (type != ANNOTATION) {
             throw new IllegalStateException("There is no annotation value");
         }
-        return (AnnotationHolder)value;
+        return (AnnotationReader)value;
     }
 
     public byte getType() {

teavm-core/src/main/java/org/teavm/model/MethodHolder.java

@@ -22,7 +22,8 @@ package org.teavm.model;
 public class MethodHolder extends MemberHolder implements MethodReader {
     private MethodDescriptor descriptor;
     private ClassHolder owner;
-    private volatile Program program;
+    private Program program;
+    private AnnotationValue annotationDefault;
 
     public MethodHolder(MethodDescriptor descriptor) {
         super(descriptor.getName());
@@ -95,4 +96,13 @@ public class MethodHolder extends MemberHolder implements MethodReader {
             this.program.setMethod(this);
         }
     }
+
+    @Override
+    public AnnotationValue getAnnotationDefault() {
+        return annotationDefault;
+    }
+
+    public void setAnnotationDefault(AnnotationValue annotationDefault) {
+        this.annotationDefault = annotationDefault;
+    }
 }

teavm-core/src/main/java/org/teavm/model/MethodReader.java

@@ -35,4 +35,6 @@ public interface MethodReader extends MemberReader {
     MethodReference getReference();
 
     ProgramReader getProgram();
+
+    AnnotationValue getAnnotationDefault();
 }

teavm-core/src/main/java/org/teavm/model/util/ModelUtils.java

@@ -52,6 +52,9 @@ public final class ModelUtils {
             copy.setProgram(ProgramUtils.copy(method.getProgram()));
         }
         copyAnnotations(method.getAnnotations(), copy.getAnnotations());
+        if (method.getAnnotationDefault() != null) {
+            copy.setAnnotationDefault(copyAnnotationValue(method.getAnnotationDefault()));
+        }
         return copy;
     }
 

teavm-core/src/main/java/org/teavm/parsing/Parser.java

@@ -53,6 +53,9 @@ public final class Parser {
         while (program.variableCount() <= method.parameterCount()) {
             program.createVariable();
         }
+        if (node.annotationDefault != null) {
+            method.setAnnotationDefault(parseAnnotationValue(node.annotationDefault));
+        }
         return method;
     }
 

teavm-tests/src/test/java/org/teavm/classlib/java/lang/ClassTest.java

@@ -119,11 +119,32 @@ public class ClassTest {
         assertTrue(TestAnnot.class.isAssignableFrom(annotations[0].getClass()));
     }
 
+    @Test
+    public void annotationFieldsExposed() {
+        AnnotWithDefaultField annot = B.class.getAnnotation(AnnotWithDefaultField.class);
+        assertEquals(2, annot.x());
+        annot = C.class.getAnnotation(AnnotWithDefaultField.class);
+        assertEquals(3, annot.x());
+    }
+
     @TestAnnot
     private static class A {
     }
 
+    @AnnotWithDefaultField
+    private static class B {
+    }
+
+    @AnnotWithDefaultField(x = 3)
+    private static class C {
+    }
+
     @Retention(RetentionPolicy.RUNTIME)
     static @interface TestAnnot {
     }
+
+    @Retention(RetentionPolicy.RUNTIME)
+    static @interface AnnotWithDefaultField {
+        int x() default 2;
+    }
 }