/*
* Copyright 2011-2017 Amazon.com, Inc. or its affiliates. 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://aws.amazon.com/apache2.0
*
* This file 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.amazonaws.services.dynamodbv2.datamodeling;
import java.lang.reflect.Method;
import java.util.Collection;
import java.util.HashMap;
import java.util.LinkedList;
import java.util.List;
import java.util.Map;
import java.util.concurrent.locks.ReentrantReadWriteLock;
import java.util.concurrent.locks.ReentrantReadWriteLock.ReadLock;
import java.util.concurrent.locks.ReentrantReadWriteLock.WriteLock;
import com.amazonaws.annotation.GuardedBy;
import com.amazonaws.annotation.SdkInternalApi;
/**
* Reflection assistant for {@link DynamoDBMapper}
*
* @deprecated This class is internal only and should not be used. It will be removed in the next
* major version of the SDK.
*/
@Deprecated
@SdkInternalApi
class DynamoDBReflector {
/*
* Several caches for performance. Collectively, they can make this class
* over twice as fast.
*/
private final Map<Class<?>, Collection<Method>> getterCache = new HashMap<Class<?>, Collection<Method>>();
private final Map<Class<?>, Method> primaryHashKeyGetterCache = new HashMap<Class<?>, Method>();
private final Map<Class<?>, Method> primaryRangeKeyGetterCache = new HashMap<Class<?>, Method>();
private final Map<Class<?>, List<Method>> primaryKeyGettersCache = new HashMap<Class<?>, List<Method>>();
/*
* All caches keyed by a Method use the getter for a particular mapped
* property
*/
private final Map<Method, Method> setterCache = new HashMap<Method, Method>();
@GuardedBy("readWriteLockAttrName")
private final Map<Method, String> attributeNameCache = new HashMap<Method, String>();
private final Map<Method, Boolean> versionAttributeGetterCache = new HashMap<Method, Boolean>();
private final Map<Method, Boolean> autoGeneratedKeyGetterCache = new HashMap<Method, Boolean>();
private final ReentrantReadWriteLock readWriteLockAttrName = new ReentrantReadWriteLock();
private final ReadLock readLockAttrName = readWriteLockAttrName.readLock();
private final WriteLock writeLockAttrName = readWriteLockAttrName.writeLock();
/**
* Returns the set of getter methods which are relevant when marshalling or
* unmarshalling an object.
*/
Collection<Method> getRelevantGetters(Class<?> clazz) {
synchronized (getterCache) {
if ( !getterCache.containsKey(clazz) ) {
List<Method> relevantGetters = findRelevantGetters(clazz);
getterCache.put(clazz, relevantGetters);
}
return getterCache.get(clazz);
}
}
static List<Method> findRelevantGetters(Class<?> clazz) {
List<Method> relevantGetters = new LinkedList<Method>();
for ( Method m : clazz.getMethods() ) {
if ( isRelevantGetter(m) ) {
relevantGetters.add(m);
}
}
return relevantGetters;
}
/**
* Returns whether the method given is a getter method we should serialize /
* deserialize to the service. The method must begin with "get" or "is",
* have no arguments, belong to a class that declares its table, and not be
* marked ignored.
*/
private static boolean isRelevantGetter(Method m) {
return (m.getName().startsWith("get") || m.getName().startsWith("is"))
&& m.getParameterTypes().length == 0
&& ! (m.isBridge() || m.isSynthetic())
&& isDocumentType(m.getDeclaringClass())
&& !ReflectionUtils.getterOrFieldHasAnnotation(m, DynamoDBIgnore.class);
}
private static boolean isDocumentType(Class<?> clazz) {
return (clazz.getAnnotation(DynamoDBTable.class) != null)
|| (clazz.getAnnotation(DynamoDBDocument.class) != null);
}
/**
* Returns the annotated {@link DynamoDBRangeKey} getter for the class
* given, or null if the class doesn't have one.
*/
<T> Method getPrimaryRangeKeyGetter(Class<T> clazz) {
synchronized (primaryRangeKeyGetterCache) {
if ( !primaryRangeKeyGetterCache.containsKey(clazz) ) {
Method rangeKeyMethod = null;
for ( Method method : getRelevantGetters(clazz) ) {
if ( method.getParameterTypes().length == 0
&& ReflectionUtils.getterOrFieldHasAnnotation(method, DynamoDBRangeKey.class)) {
rangeKeyMethod = method;
break;
}
}
primaryRangeKeyGetterCache.put(clazz, rangeKeyMethod);
}
return primaryRangeKeyGetterCache.get(clazz);
}
}
/**
* Returns all annotated {@link DynamoDBHashKey} and
* {@link DynamoDBRangeKey} getters for the class given, throwing an
* exception if there isn't one.
*/
<T> Collection<Method> getPrimaryKeyGetters(Class<T> clazz) {
synchronized (primaryKeyGettersCache) {
if ( !primaryKeyGettersCache.containsKey(clazz) ) {
List<Method> keyGetters = new LinkedList<Method>();
for (Method getter : getRelevantGetters(clazz)) {
if (ReflectionUtils.getterOrFieldHasAnnotation(getter, DynamoDBHashKey.class)
|| ReflectionUtils.getterOrFieldHasAnnotation(getter, DynamoDBRangeKey.class)) {
keyGetters.add(getter);
}
}
primaryKeyGettersCache.put(clazz, keyGetters);
}
return primaryKeyGettersCache.get(clazz);
}
}
/**
* Returns the annotated {@link DynamoDBHashKey} getter for the class given,
* throwing an exception if there isn't one.
*/
<T> Method getPrimaryHashKeyGetter(Class<T> clazz) {
Method hashKeyMethod;
synchronized (primaryHashKeyGetterCache) {
if ( !primaryHashKeyGetterCache.containsKey(clazz) ) {
for ( Method method : getRelevantGetters(clazz) ) {
if ( method.getParameterTypes().length == 0
&& ReflectionUtils.getterOrFieldHasAnnotation(method, DynamoDBHashKey.class)) {
primaryHashKeyGetterCache.put(clazz, method);
break;
}
}
}
hashKeyMethod = primaryHashKeyGetterCache.get(clazz);
}
if ( hashKeyMethod == null ) {
throw new DynamoDBMappingException("Public, zero-parameter hash key property must be annotated with "
+ DynamoDBHashKey.class);
}
return hashKeyMethod;
}
/**
* Returns the {@link DynamoDBTable} annotation of the class given, throwing
* a runtime exception if it isn't annotated.
*/
<T> DynamoDBTable getTable(Class<T> clazz) {
DynamoDBTable table = clazz.getAnnotation(DynamoDBTable.class);
if ( table == null )
throw new DynamoDBMappingException("Class " + clazz + " must be annotated with " + DynamoDBTable.class);
return table;
}
/**
* Returns the attribute name corresponding to the given getter method.
*/
String getAttributeName(Method getter) {
String attributeName;
readLockAttrName.lock();
try {
attributeName = attributeNameCache.get(getter);
} finally {
readLockAttrName.unlock();
}
if ( attributeName != null )
return attributeName;
DynamoDBHashKey hashKeyAnnotation = ReflectionUtils.getAnnotationFromGetterOrField(getter, DynamoDBHashKey.class);
if ( hashKeyAnnotation != null ) {
attributeName = hashKeyAnnotation.attributeName();
if ( attributeName != null && attributeName.length() > 0 )
return cacheAttributeName(getter, attributeName);
}
DynamoDBIndexHashKey indexHashKey = ReflectionUtils.getAnnotationFromGetterOrField(getter, DynamoDBIndexHashKey.class);
if ( indexHashKey != null ) {
attributeName = indexHashKey.attributeName();
if ( attributeName != null && attributeName.length() > 0 )
return cacheAttributeName(getter, attributeName);
}
DynamoDBRangeKey rangeKey = ReflectionUtils.getAnnotationFromGetterOrField(getter, DynamoDBRangeKey.class);
if ( rangeKey != null ) {
attributeName = rangeKey.attributeName();
if ( attributeName != null && attributeName.length() > 0 )
return cacheAttributeName(getter, attributeName);
}
DynamoDBIndexRangeKey indexRangeKey = ReflectionUtils.getAnnotationFromGetterOrField(getter, DynamoDBIndexRangeKey.class);
if ( indexRangeKey != null ) {
attributeName = indexRangeKey.attributeName();
if ( attributeName != null && attributeName.length() > 0 )
return cacheAttributeName(getter, attributeName);
}
DynamoDBAttribute attribute = ReflectionUtils.getAnnotationFromGetterOrField(getter, DynamoDBAttribute.class);
if ( attribute != null ) {
attributeName = attribute.attributeName();
if ( attributeName != null && attributeName.length() > 0 )
return cacheAttributeName(getter, attributeName);
}
DynamoDBVersionAttribute version = ReflectionUtils.getAnnotationFromGetterOrField(getter, DynamoDBVersionAttribute.class);
if ( version != null ) {
attributeName = version.attributeName();
if ( attributeName != null && attributeName.length() > 0 )
return cacheAttributeName(getter, attributeName);
}
// Default to the camel-cased field name of the getter method, inferred
// according to the Java naming convention.
attributeName = ReflectionUtils.getFieldNameByGetter(getter, true);
return cacheAttributeName(getter, attributeName);
}
private String cacheAttributeName(Method getter, String attributeName) {
writeLockAttrName.lock();
try {
attributeNameCache.put(getter, attributeName);
} finally {
writeLockAttrName.unlock();
}
return attributeName;
}
/**
* Returns the setter corresponding to the getter given, or null if no such
* setter exists.
*/
Method getSetter(Method getter) {
synchronized (setterCache) {
if ( !setterCache.containsKey(getter) ) {
String fieldName = ReflectionUtils.getFieldNameByGetter(getter, false);
String setterName = "set" + fieldName;
Method setter = null;
try {
setter = getter.getDeclaringClass().getMethod(setterName, getter.getReturnType());
} catch ( NoSuchMethodException e ) {
throw new DynamoDBMappingException("Expected a public, one-argument method called " + setterName
+ " on " + getter.getDeclaringClass(), e);
} catch ( SecurityException e ) {
throw new DynamoDBMappingException("No access to public, one-argument method called " + setterName
+ " on " + getter.getDeclaringClass(), e);
}
setterCache.put(getter, setter);
}
return setterCache.get(getter);
}
}
/**
* Returns whether the method given is an annotated, no-args getter of a
* version attribute.
*/
boolean isVersionAttributeGetter(Method getter) {
synchronized (versionAttributeGetterCache) {
if ( !versionAttributeGetterCache.containsKey(getter) ) {
versionAttributeGetterCache.put(
getter,
getter.getName().startsWith("get") && getter.getParameterTypes().length == 0
&& ReflectionUtils.getterOrFieldHasAnnotation(getter, DynamoDBVersionAttribute.class));
}
return versionAttributeGetterCache.get(getter);
}
}
/**
* Returns whether the method given is an assignable key getter.
*/
boolean isAssignableKey(Method getter) {
synchronized (autoGeneratedKeyGetterCache) {
if ( !autoGeneratedKeyGetterCache.containsKey(getter) ) {
autoGeneratedKeyGetterCache.put(
getter,
ReflectionUtils.getterOrFieldHasAnnotation(getter, DynamoDBAutoGeneratedKey.class)
&& ( ReflectionUtils.getterOrFieldHasAnnotation(getter, DynamoDBHashKey.class) ||
ReflectionUtils.getterOrFieldHasAnnotation(getter, DynamoDBRangeKey.class) ||
ReflectionUtils.getterOrFieldHasAnnotation(getter, DynamoDBIndexHashKey.class) ||
ReflectionUtils.getterOrFieldHasAnnotation(getter, DynamoDBIndexRangeKey.class)));
}
return autoGeneratedKeyGetterCache.get(getter);
}
}
/**
* Returns the name of the primary hash key.
*/
String getPrimaryHashKeyName(Class<?> clazz) {
return getAttributeName(getPrimaryHashKeyGetter(clazz));
}
/**
* Returns the name of the primary range key, or null if the table does not
* one.
*/
String getPrimaryRangeKeyName(Class<?> clazz) {
Method primaryRangeKeyGetter = getPrimaryHashKeyGetter(clazz);
return primaryRangeKeyGetter == null ?
null
:
getAttributeName(getPrimaryRangeKeyGetter(clazz));
}
/**
* Returns true if and only if the specified class has declared a
* primary range key.
*/
boolean hasPrimaryRangeKey(Class<?> clazz) {
return getPrimaryRangeKeyGetter(clazz) != null;
}
}