io.permazen.JReferenceField Maven / Gradle / Ivy
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/*
* Copyright (C) 2015 Archie L. Cobbs. All rights reserved.
*/
package io.permazen;
import com.google.common.base.Converter;
import com.google.common.reflect.TypeToken;
import io.permazen.core.DeleteAction;
import io.permazen.core.ObjId;
import io.permazen.core.type.ReferenceFieldType;
import io.permazen.schema.ReferenceSchemaField;
import java.lang.reflect.Method;
import java.util.Arrays;
import java.util.HashSet;
import java.util.TreeSet;
import java.util.stream.Collectors;
import org.objectweb.asm.ClassWriter;
import org.objectweb.asm.Label;
import org.objectweb.asm.MethodVisitor;
import org.objectweb.asm.Opcodes;
import org.objectweb.asm.Type;
/**
* Represents a reference field in a {@link JClass} or a reference sub-field of a complex field in a {@link JClass}.
*/
public class JReferenceField extends JSimpleField {
final DeleteAction onDelete;
final boolean cascadeDelete;
final boolean allowDeleted;
final boolean allowDeletedSnapshot;
final String[] forwardCascades;
final String[] inverseCascades;
JReferenceField(Permazen jdb, String name, int storageId, String description, TypeToken typeToken,
io.permazen.annotation.JField annotation, Method getter, Method setter) {
super(jdb, name, storageId, typeToken, new ReferenceFieldType(), true, annotation, description, getter, setter);
this.onDelete = annotation.onDelete();
this.cascadeDelete = annotation.cascadeDelete();
this.allowDeleted = annotation.allowDeleted();
this.allowDeletedSnapshot = annotation.allowDeletedSnapshot();
this.forwardCascades = annotation.cascades();
this.inverseCascades = annotation.inverseCascades();
}
@Override
public JObject getValue(JObject jobj) {
return (JObject)super.getValue(jobj);
}
@Override
public R visit(JFieldSwitch target) {
return target.caseJReferenceField(this);
}
@Override
public Converter getConverter(JTransaction jtx) {
return jtx.referenceConverter.reverse();
}
/**
* Get the {@link DeleteAction} configured for this field.
*
* @return this field's {@link DeleteAction}
*/
public DeleteAction getOnDelete() {
return this.onDelete;
}
/**
* Determine whether the referred-to object should be deleted when an object containing this field is deleted.
*
* @return this field's delete cascade setting
*/
public boolean isCascadeDelete() {
return this.cascadeDelete;
}
/**
* Determine whether this field allows assignment to deleted objects in normal transactions.
*
* @return this field's deleted assignment setting for normal transactions
*/
public boolean isAllowDeleted() {
return this.allowDeleted;
}
/**
* Determine whether this field allows assignment to deleted objects in snapshot transactions.
*
* @return this field's deleted assignment setting for snapshot transactions
*/
public boolean isAllowDeletedSnapshot() {
return this.allowDeletedSnapshot;
}
/**
* Get this field's forward copy cascades.
*
*
* The returned array is a copy; modifications to it have no effect.
*
* @return zero or more forward copy cascade names
*/
public String[] getForwardCascades() {
return this.forwardCascades.clone();
}
/**
* Get this field's inverse copy cascades.
*
*
* The returned array is a copy; modifications to it have no effect.
*
* @return zero or more inverse copy cascade names
*/
public String[] getInverseCascades() {
return this.inverseCascades.clone();
}
@Override
boolean isSameAs(JField that0) {
if (!super.isSameAs(that0))
return false;
final JReferenceField that = (JReferenceField)that0;
if (!this.onDelete.equals(that.onDelete))
return false;
if (this.cascadeDelete != that.cascadeDelete)
return false;
if (this.allowDeleted != that.allowDeleted)
return false;
if (this.allowDeletedSnapshot != that.allowDeletedSnapshot)
return false;
if (!new HashSet<>(Arrays.asList(this.forwardCascades)).equals(new HashSet<>(Arrays.asList(that.forwardCascades))))
return false;
if (!new HashSet<>(Arrays.asList(this.inverseCascades)).equals(new HashSet<>(Arrays.asList(that.inverseCascades))))
return false;
return true;
}
@Override
ReferenceSchemaField toSchemaItem(Permazen jdb) {
final ReferenceSchemaField schemaField = new ReferenceSchemaField();
super.initialize(jdb, schemaField);
schemaField.setOnDelete(this.onDelete);
schemaField.setCascadeDelete(this.cascadeDelete);
schemaField.setAllowDeleted(this.allowDeleted);
schemaField.setAllowDeletedSnapshot(this.allowDeletedSnapshot);
final Class rawType = this.typeToken.getRawType();
if (!rawType.isAssignableFrom(JObject.class)) {
assert !rawType.isAssignableFrom(UntypedJObject.class);
if (UntypedJObject.class.isAssignableFrom(rawType))
throw new RuntimeException("internal error: " + rawType);
schemaField.setObjectTypes(
jdb.getJClasses(rawType).stream()
.map(jclass -> jclass.storageId)
.collect(Collectors.toCollection(TreeSet::new)));
}
return schemaField;
}
// POJO import/export
@Override
Object importCoreValue(ImportContext context, Object value) {
return value != null ? context.doImportPlain(value) : null;
}
@Override
Object exportCoreValue(ExportContext context, Object value) {
return value != null ? context.doExportPlain((ObjId)value) : null;
}
// Bytecode generation
@Override
void outputMethods(final ClassGenerator generator, ClassWriter cw) {
//
// Getter:
//
// Object value = this.readCoreAPIValue();
// if (value == null)
// return null;
// ObjId id = (ObjId)value;
// return this.tx.get(id);
//
MethodVisitor mv = cw.visitMethod(
this.getter.getModifiers() & (Opcodes.ACC_PUBLIC | Opcodes.ACC_PROTECTED),
this.getter.getName(), Type.getMethodDescriptor(this.getter), null, generator.getExceptionNames(this.getter));
this.outputReadCoreValueBytecode(generator, mv);
mv.visitInsn(Opcodes.DUP);
final Label label1 = new Label();
mv.visitJumpInsn(Opcodes.IFNONNULL, label1);
mv.visitInsn(Opcodes.POP);
mv.visitInsn(Opcodes.ACONST_NULL);
mv.visitInsn(Opcodes.ARETURN);
mv.visitLabel(label1);
mv.visitFrame(Opcodes.F_SAME1, 0, new Object[0], 1, new String[] { Type.getInternalName(Object.class) });
mv.visitTypeInsn(Opcodes.CHECKCAST, Type.getInternalName(ObjId.class));
mv.visitVarInsn(Opcodes.ALOAD, 0);
mv.visitFieldInsn(Opcodes.GETFIELD, generator.getClassName(),
ClassGenerator.TX_FIELD_NAME, Type.getDescriptor(JTransaction.class));
mv.visitInsn(Opcodes.SWAP);
generator.emitInvoke(mv, ClassGenerator.JTRANSACTION_GET_METHOD);
mv.visitTypeInsn(Opcodes.CHECKCAST, Type.getInternalName(this.getter.getReturnType()));
mv.visitInsn(Opcodes.ARETURN);
mv.visitMaxs(0, 0);
mv.visitEnd();
//
// Setter:
//
// ObjId id;
// if (jobj == null)
// id = null;
// else
// id = jobj.getObjId();
// this.writeCoreAPIValue(id);
//
mv = cw.visitMethod(
this.setter.getModifiers() & (Opcodes.ACC_PUBLIC | Opcodes.ACC_PROTECTED),
this.setter.getName(), Type.getMethodDescriptor(this.setter), null, generator.getExceptionNames(this.setter));
mv.visitVarInsn(Opcodes.ALOAD, 1);
final Label label2 = new Label();
final Label label3 = new Label();
mv.visitJumpInsn(Opcodes.IFNONNULL, label2);
mv.visitInsn(Opcodes.ACONST_NULL);
mv.visitJumpInsn(Opcodes.GOTO, label3);
mv.visitLabel(label2);
mv.visitFrame(Opcodes.F_SAME, 0, new Object[0], 0, new Object[0]);
mv.visitVarInsn(Opcodes.ALOAD, 1);
generator.emitInvoke(mv, ClassGenerator.JOBJECT_GET_OBJ_ID_METHOD);
mv.visitLabel(label3);
mv.visitFrame(Opcodes.F_SAME1, 0, new Object[0], 1, new String[] { Type.getInternalName(ObjId.class) });
//mv.visitTypeInsn(Opcodes.CHECKCAST, Type.getInternalName(ObjId.class));
this.outputWriteCoreValueBytecode(generator, mv);
mv.visitInsn(Opcodes.RETURN);
mv.visitMaxs(0, 0);
mv.visitEnd();
}
}