com.hazelcast.query.impl.getters.ReflectionHelper Maven / Gradle / Ivy
/*
* Copyright (c) 2008-2016, Hazelcast, Inc. All Rights Reserved.
*
* 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.hazelcast.query.impl.getters;
import com.hazelcast.query.QueryException;
import com.hazelcast.query.impl.AttributeType;
import com.hazelcast.query.impl.IndexImpl;
import com.hazelcast.util.EmptyStatement;
import com.hazelcast.util.ExceptionUtil;
import java.lang.reflect.Field;
import java.lang.reflect.Method;
import java.math.BigDecimal;
import java.math.BigInteger;
import java.sql.Timestamp;
import java.util.ArrayList;
import java.util.Date;
import java.util.List;
import java.util.UUID;
import static com.hazelcast.query.QueryConstants.THIS_ATTRIBUTE_NAME;
import static com.hazelcast.query.impl.getters.NullGetter.NULL_GETTER;
import static com.hazelcast.query.impl.getters.SuffixModifierUtils.getModifierSuffix;
import static com.hazelcast.query.impl.getters.SuffixModifierUtils.removeModifierSuffix;
/**
* Scans your classpath, indexes the metadata, allows you to query it on runtime.
*/
public final class ReflectionHelper {
static final ClassLoader THIS_CL = ReflectionHelper.class.getClassLoader();
private static final int INITIAL_CAPACITY = 3;
// we don't want instances
private ReflectionHelper() {
}
public static AttributeType getAttributeType(Class klass) {
if (klass == null) {
return null;
}
if (klass == String.class) {
return AttributeType.STRING;
} else if (klass == int.class || klass == Integer.class) {
return AttributeType.INTEGER;
} else if (klass == short.class || klass == Short.class) {
return AttributeType.SHORT;
} else if (klass == long.class || klass == Long.class) {
return AttributeType.LONG;
} else if (klass == boolean.class || klass == Boolean.class) {
return AttributeType.BOOLEAN;
} else if (klass == double.class || klass == Double.class) {
return AttributeType.DOUBLE;
} else if (klass == BigDecimal.class) {
return AttributeType.BIG_DECIMAL;
} else if (klass == BigInteger.class) {
return AttributeType.BIG_INTEGER;
} else if (klass == float.class || klass == Float.class) {
return AttributeType.FLOAT;
} else if (klass == byte.class || klass == Byte.class) {
return AttributeType.BYTE;
} else if (klass == char.class || klass == Character.class) {
return AttributeType.CHAR;
} else if (klass == Timestamp.class) {
return AttributeType.SQL_TIMESTAMP;
} else if (klass == java.sql.Date.class) {
return AttributeType.SQL_DATE;
} else if (klass == Date.class) {
return AttributeType.DATE;
} else if (klass.isEnum()) {
return AttributeType.ENUM;
} else if (klass == UUID.class) {
return AttributeType.UUID;
}
return null;
}
public static Getter createGetter(Object obj, String attribute) {
if (obj == null || obj == IndexImpl.NULL) {
return NULL_GETTER;
}
final Class targetClazz = obj.getClass();
Class clazz = targetClazz;
Getter getter;
try {
Getter parent = null;
List possibleMethodNames = new ArrayList(INITIAL_CAPACITY);
for (final String fullname : attribute.split("\\.")) {
String baseName = removeModifierSuffix(fullname);
String modifier = getModifierSuffix(fullname, baseName);
Getter localGetter = null;
possibleMethodNames.clear();
possibleMethodNames.add(baseName);
final String camelName = Character.toUpperCase(baseName.charAt(0)) + baseName.substring(1);
possibleMethodNames.add("get" + camelName);
possibleMethodNames.add("is" + camelName);
if (baseName.equals(THIS_ATTRIBUTE_NAME.value())) {
localGetter = GetterFactory.newThisGetter(parent, obj);
} else {
if (parent != null) {
clazz = parent.getReturnType();
}
for (String methodName : possibleMethodNames) {
try {
final Method method = clazz.getMethod(methodName);
method.setAccessible(true);
localGetter = GetterFactory.newMethodGetter(obj, parent, method, modifier);
if (localGetter == NULL_GETTER) {
return localGetter;
}
clazz = method.getReturnType();
break;
} catch (NoSuchMethodException ignored) {
EmptyStatement.ignore(ignored);
}
}
if (localGetter == null) {
try {
final Field field = clazz.getField(baseName);
localGetter = GetterFactory.newFieldGetter(obj, parent, field, modifier);
if (localGetter == NULL_GETTER) {
return localGetter;
}
clazz = field.getType();
} catch (NoSuchFieldException ignored) {
EmptyStatement.ignore(ignored);
}
}
if (localGetter == null) {
Class c = clazz;
while (!c.isInterface() && !Object.class.equals(c)) {
try {
final Field field = c.getDeclaredField(baseName);
field.setAccessible(true);
localGetter = GetterFactory.newFieldGetter(obj, parent, field, modifier);
if (localGetter == NULL_GETTER) {
return NULL_GETTER;
}
clazz = field.getType();
break;
} catch (NoSuchFieldException ignored) {
c = c.getSuperclass();
}
}
}
}
if (localGetter == null) {
throw new IllegalArgumentException("There is no suitable accessor for '"
+ baseName + "' on class '" + clazz + "'");
}
parent = localGetter;
}
getter = parent;
return getter;
} catch (Throwable e) {
throw new QueryException(e);
}
}
public static Object extractValue(Object object, String attributeName) throws Exception {
return createGetter(object, attributeName).getValue(object);
}
public static T invokeMethod(Object object, String methodName) throws RuntimeException {
try {
Method method = object.getClass().getMethod(methodName);
method.setAccessible(true);
return (T) method.invoke(object);
} catch (Exception e) {
throw ExceptionUtil.rethrow(e);
}
}
}