diff options
| -rw-r--r-- | src/main/java/com/amazon/carbonado/util/Converter.java | 116 |
1 files changed, 90 insertions, 26 deletions
diff --git a/src/main/java/com/amazon/carbonado/util/Converter.java b/src/main/java/com/amazon/carbonado/util/Converter.java index 33278a4..b15d408 100644 --- a/src/main/java/com/amazon/carbonado/util/Converter.java +++ b/src/main/java/com/amazon/carbonado/util/Converter.java @@ -18,6 +18,7 @@ package com.amazon.carbonado.util;
+import java.lang.reflect.Constructor;
import java.lang.reflect.Method;
import java.lang.reflect.Modifier;
@@ -49,15 +50,36 @@ import org.cojen.util.SoftValuedHashMap; * @since 1.2
*/
public abstract class Converter {
- private static final Map<Class, Converter> cCache = new SoftValuedHashMap();
+ private static final Map<Class, Class<? extends Converter>> cCache = new SoftValuedHashMap();
- public static synchronized <C extends Converter> C build(Class<C> converterType) {
- C converter = (C) cCache.get(converterType);
- if (converter == null) {
- converter = new Builder<C>(converterType).build();
- cCache.put(converterType, converter);
+ /**
+ * @param converterType type of converter to generate
+ * @throws IllegalArgumentException if converter doesn't a no-arg constructor
+ */
+ public static <C extends Converter> C build(Class<C> converterType) {
+ try {
+ return buildClass(converterType).newInstance();
+ } catch (InstantiationException e) {
+ throw new IllegalArgumentException
+ ("TypeConverter must have a public no-arg constructor: " + converterType);
+ } catch (IllegalAccessException e) {
+ // Not expected to happen, since generated constructors are public.
+ throw new IllegalArgumentException(e);
+ }
+ }
+
+ /**
+ * @param converterType type of converter to generate
+ */
+ public static synchronized <C extends Converter> Class<? extends C> buildClass
+ (Class<C> converterType)
+ {
+ Class<? extends C> converterClass = (Class<? extends C>) cCache.get(converterType);
+ if (converterClass == null) {
+ converterClass = new Builder<C>(converterType).buildClass();
+ cCache.put(converterType, converterClass);
}
- return converter;
+ return converterClass;
}
/**
@@ -161,13 +183,6 @@ public abstract class Converter { throw new IllegalArgumentException("Not a TypeConverter: " + converterType);
}
- try {
- converterType.getConstructor();
- } catch (NoSuchMethodException e) {
- throw new IllegalArgumentException
- ("TypeConverter must have a public no-arg constructor: " + converterType);
- }
-
mConverterType = converterType;
mConvertMap = new HashMap<Class, Map<Class, Method>>();
@@ -235,7 +250,7 @@ public abstract class Converter { */
}
- C build() {
+ Class<? extends C> buildClass() {
ClassInjector ci = ClassInjector
.create(mConverterType.getName(), mConverterType.getClassLoader());
@@ -244,7 +259,36 @@ public abstract class Converter { mClassFile.setSourceFile(Converter.class.getName());
mClassFile.setTarget("1.5");
- mClassFile.addDefaultConstructor();
+ // Add constructors which match superclass.
+ int ctorCount = 0;
+ for (Constructor ctor : mConverterType.getDeclaredConstructors()) {
+ int modifiers = ctor.getModifiers();
+ if (!Modifier.isPublic(modifiers) && !Modifier.isProtected(modifiers)) {
+ continue;
+ }
+
+ ctorCount++;
+
+ TypeDesc[] params = new TypeDesc[ctor.getParameterTypes().length];
+ for (int i=0; i<params.length; i++) {
+ params[i] = TypeDesc.forClass(ctor.getParameterTypes()[i]);
+ }
+
+ MethodInfo mi = mClassFile.addConstructor(Modifiers.PUBLIC, params);
+ CodeBuilder b = new CodeBuilder(mi);
+
+ b.loadThis();
+ for (int i=0; i<params.length; i++) {
+ b.loadLocal(b.getParameter(0));
+ }
+ b.invokeSuperConstructor(params);
+ b.returnVoid();
+ }
+
+ if (ctorCount == 0) {
+ throw new IllegalArgumentException
+ ("TypeConverter has no public or protected constructors: " + mConverterType);
+ }
addPrimitiveConvertMethod(byte.class);
addPrimitiveConvertMethod(short.class);
@@ -269,15 +313,7 @@ public abstract class Converter { addConversionSwitch(b, null);
}
- Class clazz = ci.defineClass(mClassFile);
-
- try {
- return (C) clazz.newInstance();
- } catch (IllegalAccessException e) {
- throw new RuntimeException(e);
- } catch (InstantiationException e) {
- throw new RuntimeException(e);
- }
+ return ci.defineClass(mClassFile);
}
private void addPrimitiveConvertMethod(Class fromType) {
@@ -418,7 +454,7 @@ public abstract class Converter { b.convert(fromTypeDesc, TypeDesc.forClass(paramType));
b.invoke(convertMethod);
TypeDesc retType = TypeDesc.forClass(convertMethod.getReturnType());
- b.convert(retType, retType.toObjectType());
+ b.convert(retType, toTypeDesc.toObjectType());
}
b.returnValue(TypeDesc.OBJECT);
@@ -484,6 +520,34 @@ public abstract class Converter { }
private void addAutomaticConversion(Class fromType, Class toType, Method method) {
+ if (method != null) {
+ Class paramType = method.getParameterTypes()[0];
+ if (!paramType.isAssignableFrom(fromType)) {
+ if (!fromType.isPrimitive() && paramType.isPrimitive()) {
+ // Reject because unboxing could result in NullPointerException.
+ return;
+ }
+ if (!new ConversionComparator(fromType).isConversionPossible(paramType)) {
+ // Reject.
+ return;
+ }
+ }
+
+ Class returnType = method.getReturnType();
+ if (!toType.isAssignableFrom(returnType)) {
+ if (!returnType.isPrimitive() && toType.isPrimitive()) {
+ // Reject because unboxing could result in NullPointerException.
+ return;
+ }
+ if (TypeDesc.forClass(returnType).toObjectType() !=
+ TypeDesc.forClass(toType).toObjectType())
+ {
+ // Reject widening or narrowing return type.
+ return;
+ }
+ }
+ }
+
addConversionIfNotExists(fromType, toType, method);
// Add no-op conversions.
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