com.blazebit.persistence.impl.SplittingParameterTransformer Maven / Gradle / Ivy
/*
* Copyright 2014 - 2020 Blazebit.
*
* 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 com.blazebit.persistence.impl;
import com.blazebit.persistence.parser.EntityMetamodel;
import com.blazebit.persistence.parser.util.JpaMetamodelUtils;
import com.blazebit.reflection.ReflectionUtils;
import javax.persistence.Query;
import javax.persistence.metamodel.Attribute;
import javax.persistence.metamodel.ManagedType;
import java.lang.reflect.Field;
import java.lang.reflect.Member;
import java.lang.reflect.Method;
import java.util.List;
import java.util.Map;
/**
* @author Christian Beikov
* @since 1.3.0
*/
public class SplittingParameterTransformer implements ParameterValueTransformer {
private final ParameterManager parameterManager;
private final String[] parameterNames;
private final Field[][] fields;
private final Method[][] getters;
public SplittingParameterTransformer(ParameterManager parameterManager, EntityMetamodel metamodel, Class parameterType, Map> parameterAccessPaths) {
try {
this.parameterManager = parameterManager;
this.parameterNames = parameterAccessPaths.keySet().toArray(new String[parameterAccessPaths.size()]);
Field[][] fields = new Field[parameterAccessPaths.size()][];
Method[][] getters = new Method[parameterAccessPaths.size()][];
int i = 0;
for (List accessPath : parameterAccessPaths.values()) {
ManagedType t = metamodel.getManagedType(parameterType);
fields[i] = new Field[accessPath.size()];
getters[i] = new Method[accessPath.size()];
int j = 0;
for (String property : accessPath) {
Attribute attribute = t.getAttribute(property);
Member member = attribute.getJavaMember();
if (member instanceof Method) {
Method getter = ReflectionUtils.getGetter(t.getJavaType(), attribute.getName());
getter.setAccessible(true);
getters[i][j++] = getter;
} else if (member instanceof Field) {
Field field = (Field) member;
field.setAccessible(true);
fields[i][j++] = field;
} else {
throw new IllegalArgumentException("Unsupported attribute member type [" + member + "] for attribute [" + attribute.getName() + "] of class [" + t.getJavaType().getName() + "]");
}
t = metamodel.getManagedType(JpaMetamodelUtils.resolveFieldClass(t.getJavaType(), attribute));
}
i++;
}
this.fields = fields;
this.getters = getters;
} catch (Exception e) {
throw new IllegalArgumentException("The parameter splitter for the managed type [" + parameterType.getName() + "] could not be initialized!", e);
}
}
@Override
public ParameterValueTransformer forQuery(final Query query) {
return new ParameterValueTransformer() {
@Override
public ParameterValueTransformer forQuery(Query query) {
return SplittingParameterTransformer.this.forQuery(query);
}
@Override
public Object transform(Object originalValue) {
try {
for (int i = 0; i < parameterNames.length; i++) {
Object o = originalValue;
if (o != null) {
Field[] fieldAccess = fields[i];
Method[] methodAccess = getters[i];
for (int j = 0; j < fieldAccess.length; j++) {
if (fieldAccess[j] != null) {
o = fieldAccess[j].get(o);
} else {
o = methodAccess[j].invoke(o);
}
if (o == null) {
break;
}
}
}
query.setParameter(parameterNames[i], o);
}
return originalValue;
} catch (Exception ex) {
throw new IllegalArgumentException("Could not split parameter value [" + originalValue + "]", ex);
}
}
};
}
public String[] getParameterNames() {
return parameterNames;
}
@Override
public Object transform(Object originalValue) {
try {
for (int i = 0; i < parameterNames.length; i++) {
Field[] fieldAccess = fields[i];
Method[] methodAccess = getters[i];
Object o = originalValue;
for (int j = 0; j < fieldAccess.length; j++) {
if (fieldAccess[j] != null) {
o = fieldAccess[j].get(o);
} else {
o = methodAccess[j].invoke(o);
}
if (o == null) {
break;
}
}
parameterManager.satisfyParameter(parameterNames[i], o);
}
return originalValue;
} catch (Exception ex) {
throw new IllegalArgumentException("Could not split parameter value [" + originalValue + "]", ex);
}
}
}