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jfirebaughjfirebaugh
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Add Box/Unbox
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2 files changed

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‎include/jni/boxing.hpp

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#pragma once
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#include <jni/class.hpp>
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namespace jni
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{
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template < class > struct Boxer;
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template < class > struct Unboxer;
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template < class Unboxed >
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auto Box(JNIEnv& env, Unboxed&& unboxed)
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{
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return Boxer<typename std::decay<Unboxed>::type>().Box(env, std::forward<Unboxed>(unboxed));
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}
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template < class Tag >
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auto Unbox(JNIEnv& env, const Object<Tag>& boxed)
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{
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return Unboxer<Tag>().Unbox(env, boxed);
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}
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struct BooleanTag
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{
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static constexpr auto Name() { return "java/lang/Boolean"; }
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static constexpr auto BoxStaticMethodName() { return "valueOf"; }
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static constexpr auto UnboxMethodName() { return "booleanValue"; }
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};
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struct ByteTag
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{
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static constexpr auto Name() { return "java/lang/Byte"; }
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static constexpr auto BoxStaticMethodName() { return "valueOf"; }
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static constexpr auto UnboxMethodName() { return "byteValue"; }
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};
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struct CharacterTag
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{
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static constexpr auto Name() { return "java/lang/Character"; }
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static constexpr auto BoxStaticMethodName() { return "valueOf"; }
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static constexpr auto UnboxMethodName() { return "charValue"; }
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};
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struct ShortTag
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{
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static constexpr auto Name() { return "java/lang/Short"; }
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static constexpr auto BoxStaticMethodName() { return "valueOf"; }
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static constexpr auto UnboxMethodName() { return "shortValue"; }
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};
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struct IntegerTag
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{
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static constexpr auto Name() { return "java/lang/Integer"; }
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static constexpr auto BoxStaticMethodName() { return "valueOf"; }
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static constexpr auto UnboxMethodName() { return "intValue"; }
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};
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struct LongTag
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{
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static constexpr auto Name() { return "java/lang/Long"; }
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static constexpr auto BoxStaticMethodName() { return "valueOf"; }
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static constexpr auto UnboxMethodName() { return "longValue"; }
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};
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struct FloatTag
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{
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static constexpr auto Name() { return "java/lang/Float"; }
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static constexpr auto BoxStaticMethodName() { return "valueOf"; }
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static constexpr auto UnboxMethodName() { return "floatValue"; }
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};
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struct DoubleTag
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{
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static constexpr auto Name() { return "java/lang/Double"; }
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static constexpr auto BoxStaticMethodName() { return "valueOf"; }
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static constexpr auto UnboxMethodName() { return "doubleValue"; }
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};
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template < class Tag, class Unboxed >
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struct PrimitiveTypeBoxer
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{
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Object<Tag> Box(JNIEnv& env, Unboxed unboxed) const
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{
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static auto klass = Class<Tag>::Singleton(env);
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static auto box = klass.template GetStaticMethod<Object<Tag> (Unboxed)>(env, Tag::BoxStaticMethodName());
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return klass.Call(env, box, unboxed);
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}
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};
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template <> struct Boxer< jboolean > : PrimitiveTypeBoxer< BooleanTag , jboolean > {};
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template <> struct Boxer< jbyte > : PrimitiveTypeBoxer< ByteTag , jbyte > {};
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template <> struct Boxer< jchar > : PrimitiveTypeBoxer< CharacterTag , jchar > {};
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template <> struct Boxer< jshort > : PrimitiveTypeBoxer< ShortTag , jshort > {};
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template <> struct Boxer< jint > : PrimitiveTypeBoxer< IntegerTag , jint > {};
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template <> struct Boxer< jlong > : PrimitiveTypeBoxer< LongTag , jlong > {};
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template <> struct Boxer< jfloat > : PrimitiveTypeBoxer< FloatTag , jfloat > {};
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template <> struct Boxer< jdouble > : PrimitiveTypeBoxer< DoubleTag , jdouble > {};
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template < class Tag, class Unboxed >
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struct PrimitiveTypeUnboxer
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{
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Unboxed Unbox(JNIEnv& env, const Object<Tag>& boxed) const
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{
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static auto klass = Class<Tag>::Singleton(env);
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static auto unbox = klass.template GetMethod<Unboxed ()>(env, Tag::UnboxMethodName());
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return boxed.Call(env, unbox);
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}
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};
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template <> struct Unboxer< BooleanTag > : PrimitiveTypeUnboxer< BooleanTag , jboolean > {};
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template <> struct Unboxer< ByteTag > : PrimitiveTypeUnboxer< ByteTag , jbyte > {};
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template <> struct Unboxer< CharacterTag > : PrimitiveTypeUnboxer< CharacterTag , jchar > {};
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template <> struct Unboxer< ShortTag > : PrimitiveTypeUnboxer< ShortTag , jshort > {};
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template <> struct Unboxer< IntegerTag > : PrimitiveTypeUnboxer< IntegerTag , jint > {};
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template <> struct Unboxer< LongTag > : PrimitiveTypeUnboxer< LongTag , jlong > {};
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template <> struct Unboxer< FloatTag > : PrimitiveTypeUnboxer< FloatTag , jfloat > {};
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template <> struct Unboxer< DoubleTag > : PrimitiveTypeUnboxer< DoubleTag , jdouble > {};
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template < class Tag >
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struct Boxer<jni::Object<Tag>>
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{
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const Object<Tag>& Box(JNIEnv&, const jni::Object<Tag>& o) const { return o; }
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};
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template < class Tag >
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struct Unboxer
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{
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const Object<Tag>& Unbox(JNIEnv&, const jni::Object<Tag>& o) const { return o; }
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};
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}

‎include/jni/jni.hpp

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#include <jni/field.hpp>
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#include <jni/static_field.hpp>
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#include <jni/native_method.hpp>
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#include <jni/boxing.hpp>

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