jnr.ffi.provider.jffi.ReflectionVariableAccessorGenerator Maven / Gradle / Ivy
Go to download
Show more of this group Show more artifacts with this name
Show all versions of jnr-ffi Show documentation
Show all versions of jnr-ffi Show documentation
A library for invoking native functions from java
The newest version!
/*
* Copyright (C) 2012 Wayne Meissner
*
* This file is part of the JNR project.
*
* Licensed under the Apache License, Version 2.0 (the "License");
* you may not use this file except in compliance with the License.
* You may obtain a copy of the License at
*
* http://www.apache.org/licenses/LICENSE-2.0
*
* Unless required by applicable law or agreed to in writing, software
* distributed under the License is distributed on an "AS IS" BASIS,
* WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
* See the License for the specific language governing permissions and
* limitations under the License.
*/
package jnr.ffi.provider.jffi;
import jnr.ffi.NativeType;
import jnr.ffi.Pointer;
import jnr.ffi.Variable;
import jnr.ffi.mapper.DataConverter;
import jnr.ffi.mapper.DefaultSignatureType;
import jnr.ffi.mapper.FromNativeContext;
import jnr.ffi.mapper.FromNativeConverter;
import jnr.ffi.mapper.SignatureType;
import jnr.ffi.mapper.SignatureTypeMapper;
import jnr.ffi.mapper.ToNativeConverter;
import java.lang.annotation.Annotation;
import java.lang.reflect.Method;
import java.lang.reflect.ParameterizedType;
import java.util.Collection;
import static jnr.ffi.provider.jffi.DefaultInvokerFactory.getNumberDataConverter;
import static jnr.ffi.provider.jffi.DefaultInvokerFactory.getNumberResultConverter;
import static jnr.ffi.provider.jffi.NumberUtil.sizeof;
/**
*
*/
class ReflectionVariableAccessorGenerator {
static Variable createVariableAccessor(jnr.ffi.Runtime runtime, Method method, long symbolAddress, SignatureTypeMapper typeMapper, Collection annotations) {
java.lang.reflect.Type variableType = ((ParameterizedType) method.getGenericReturnType()).getActualTypeArguments()[0];
if (!(variableType instanceof Class)) {
throw new IllegalArgumentException("unsupported variable class: " + variableType);
}
Class javaType = (Class) variableType;
SimpleNativeContext context = new SimpleNativeContext(runtime, annotations);
SignatureType signatureType = DefaultSignatureType.create(javaType, (FromNativeContext) context);
jnr.ffi.mapper.FromNativeType mappedFromNativeType = typeMapper.getFromNativeType(signatureType, context);
FromNativeConverter fromNativeConverter = mappedFromNativeType != null ? mappedFromNativeType.getFromNativeConverter() : null;
jnr.ffi.mapper.ToNativeType mappedToNativeType = typeMapper.getToNativeType(signatureType, context);
ToNativeConverter toNativeConverter = mappedToNativeType != null ? mappedToNativeType.getToNativeConverter() : null;
Class boxedType = toNativeConverter != null ? toNativeConverter.nativeType() : javaType;
NativeType nativeType = Types.getType(runtime, boxedType, annotations).getNativeType();
jnr.ffi.provider.ToNativeType toNativeType = new jnr.ffi.provider.ToNativeType(javaType, nativeType, annotations, toNativeConverter, null);
jnr.ffi.provider.FromNativeType fromNativeType = new jnr.ffi.provider.FromNativeType(javaType, nativeType, annotations, fromNativeConverter, null);
Variable variable;
Pointer memory = MemoryUtil.newPointer(runtime, symbolAddress);
variable = getNativeVariableAccessor(memory, toNativeType, fromNativeType);
return toNativeType.getToNativeConverter() != null
? getConvertingVariable(variable, toNativeType.getToNativeConverter(), fromNativeType.getFromNativeConverter())
: variable;
}
static Variable getConvertingVariable(Variable nativeVariable, ToNativeConverter toNativeConverter, FromNativeConverter fromNativeConverter) {
if ((toNativeConverter != null && fromNativeConverter == null) || toNativeConverter == null && fromNativeConverter != null) {
throw new UnsupportedOperationException("convertible types must have both a ToNativeConverter and a FromNativeConverter");
}
return new ConvertingVariable(nativeVariable, toNativeConverter, fromNativeConverter);
}
static Variable getNativeVariableAccessor(Pointer memory, jnr.ffi.provider.ToNativeType toNativeType, jnr.ffi.provider.FromNativeType fromNativeType) {
if (Pointer.class == toNativeType.effectiveJavaType()) {
return new PointerVariable(memory);
} else if (Number.class.isAssignableFrom(toNativeType.effectiveJavaType())) {
return new NumberVariable(memory, getPointerOp(toNativeType.getNativeType()),
getNumberDataConverter(toNativeType.getNativeType()), getNumberResultConverter(fromNativeType));
} else {
throw new UnsupportedOperationException("unsupported variable type: " + toNativeType.effectiveJavaType());
}
}
private static PointerOp getPointerOp(NativeType nativeType) {
switch (nativeType) {
case SCHAR:
case UCHAR:
return Int8PointerOp.INSTANCE;
case SSHORT:
case USHORT:
return Int16PointerOp.INSTANCE;
case SINT:
case UINT:
return Int32PointerOp.INSTANCE;
case SLONGLONG:
case ULONGLONG:
return Int64PointerOp.INSTANCE;
case SLONG:
case ULONG:
case ADDRESS:
return sizeof(nativeType) == 4 ? Int32PointerOp.INSTANCE : Int64PointerOp.INSTANCE;
case FLOAT:
return FloatPointerOp.INSTANCE;
case DOUBLE:
return DoublePointerOp.INSTANCE;
}
throw new UnsupportedOperationException("cannot convert " + nativeType);
}
private static abstract class AbstractVariable implements Variable {
protected final Pointer memory;
protected AbstractVariable(Pointer memory) {
this.memory = memory;
}
}
private static final class ConvertingVariable implements Variable {
private final Variable variable;
private final ToNativeConverter toNativeConverter;
private final FromNativeConverter fromNativeConverter;
private ConvertingVariable(Variable variable, ToNativeConverter toNativeConverter, FromNativeConverter fromNativeConverter) {
this.variable = variable;
this.toNativeConverter = toNativeConverter;
this.fromNativeConverter = fromNativeConverter;
}
@Override
public Object get() {
return fromNativeConverter.fromNative(variable.get(), null);
}
@Override
public void set(Object value) {
variable.set(toNativeConverter.toNative(value, null));
}
}
private static final class NumberVariable extends AbstractVariable {
private final DataConverter dataConverter;
private final DefaultInvokerFactory.ResultConverter resultConverter;
private final PointerOp pointerOp;
private NumberVariable(Pointer memory, PointerOp pointerOp,
DataConverter dataConverter,
DefaultInvokerFactory.ResultConverter resultConverter) {
super(memory);
this.pointerOp = pointerOp;
this.dataConverter = dataConverter;
this.resultConverter = resultConverter;
}
@Override
public Number get() {
return resultConverter.fromNative(dataConverter.fromNative(pointerOp.get(memory), null), null);
}
@Override
public void set(Number value) {
pointerOp.put(memory, dataConverter.toNative(value, null));
}
}
private static final class PointerVariable extends AbstractVariable {
private PointerVariable(Pointer memory) {
super(memory);
}
public Pointer get() {
return memory.getPointer(0);
}
public void set(Pointer value) {
if (value != null) memory.putPointer(0, value); else memory.putAddress(0, 0L);
}
}
private static interface PointerOp {
public T get(Pointer memory);
public void put(Pointer memory, T value);
}
private static final class Int8PointerOp implements PointerOp {
static final PointerOp INSTANCE = new Int8PointerOp();
@Override
public Number get(Pointer memory) {
return memory.getByte(0);
}
@Override
public void put(Pointer memory, Number value) {
memory.putByte(0, value.byteValue());
}
}
private static final class Int16PointerOp implements PointerOp {
static final PointerOp INSTANCE = new Int16PointerOp();
@Override
public Number get(Pointer memory) {
return memory.getShort(0);
}
@Override
public void put(Pointer memory, Number value) {
memory.putShort(0, value.shortValue());
}
}
private static final class Int32PointerOp implements PointerOp {
static final PointerOp INSTANCE = new Int32PointerOp();
@Override
public Number get(Pointer memory) {
return memory.getInt(0);
}
@Override
public void put(Pointer memory, Number value) {
memory.putInt(0, value.intValue());
}
}
private static final class Int64PointerOp implements PointerOp {
static final PointerOp INSTANCE = new Int64PointerOp();
@Override
public Number get(Pointer memory) {
return memory.getLongLong(0);
}
@Override
public void put(Pointer memory, Number value) {
memory.putLongLong(0, value.longValue());
}
}
private static final class FloatPointerOp implements PointerOp {
static final PointerOp INSTANCE = new FloatPointerOp();
@Override
public Number get(Pointer memory) {
return memory.getFloat(0);
}
@Override
public void put(Pointer memory, Number value) {
memory.putFloat(0, value.floatValue());
}
}
private static final class DoublePointerOp implements PointerOp {
static final PointerOp INSTANCE = new DoublePointerOp();
@Override
public Number get(Pointer memory) {
return memory.getFloat(0);
}
@Override
public void put(Pointer memory, Number value) {
memory.putFloat(0, value.floatValue());
}
}
}