Spring/spring-framework
1
0
Fork 0
Code Issues Packages Projects Releases Wiki Activity

SPR-6984: auto grow collections on write through indexer

Browse Source
This commit is contained in:
Andy Clement
2010-03-15 18:15:48 +00:00
parent 0cb7e4dcb3
commit d932c043da
4 changed files with 107 additions and 25 deletions
Download Patch File Download Diff File Expand all files Collapse all files

62
org.springframework.expression/src/main/java/org/springframework/expression/spel/ast/Indexer.java
View File

@@ -61,7 +61,6 @@ public class Indexer extends SpelNodeImpl {
super(pos, expr);
}
@SuppressWarnings("unchecked")
@Override
public TypedValue getValueInternal(ExpressionState state) throws EvaluationException {
TypedValue context = state.getActiveContextObject();
@@ -119,28 +118,7 @@ public class Indexer extends SpelNodeImpl {
} else if (targetObject instanceof Collection) {
Collection c = (Collection) targetObject;
if (idx >= c.size()) {
if (state.getConfiguration().isAutoGrowCollections()) {
// Grow the collection
Object newCollectionElement = null;
try {
int newElements = idx-c.size();
Class elementClass = targetObjectTypeDescriptor.getElementType();
if (elementClass == null) {
throw new SpelEvaluationException(getStartPosition(), SpelMessage.UNABLE_TO_GROW_COLLECTION_UNKNOWN_ELEMENT_TYPE);
}
while (newElements>0) {
c.add(elementClass.newInstance());
newElements--;
}
newCollectionElement = targetObjectTypeDescriptor.getElementType().newInstance();
}
catch (Exception ex) {
throw new SpelEvaluationException(getStartPosition(), ex, SpelMessage.UNABLE_TO_GROW_COLLECTION);
}
c.add(newCollectionElement);
return new TypedValue(newCollectionElement,TypeDescriptor.valueOf(targetObjectTypeDescriptor.getElementType()));
}
else {
if (!growCollection(state, targetObjectTypeDescriptor.getElementType(), idx, c)) {
throw new SpelEvaluationException(getStartPosition(),SpelMessage.COLLECTION_INDEX_OUT_OF_BOUNDS, c.size(), idx);
}
}
@@ -234,7 +212,9 @@ public class Indexer extends SpelNodeImpl {
int idx = (Integer)state.convertValue(index, TypeDescriptor.valueOf(Integer.class));
Collection c = (Collection) targetObject;
if (idx >= c.size()) {
throw new SpelEvaluationException(getStartPosition(),SpelMessage.COLLECTION_INDEX_OUT_OF_BOUNDS, c.size(), idx);
if (!growCollection(state, targetObjectTypeDescriptor.getElementType(), idx, c)) {
throw new SpelEvaluationException(getStartPosition(),SpelMessage.COLLECTION_INDEX_OUT_OF_BOUNDS, c.size(), idx);
}
}
if (targetObject instanceof List) {
List list = (List)targetObject;
@@ -282,6 +262,40 @@ public class Indexer extends SpelNodeImpl {
throw new SpelEvaluationException(getStartPosition(),SpelMessage.INDEXING_NOT_SUPPORTED_FOR_TYPE, targetObjectTypeDescriptor.asString());
}
/**
* Attempt to grow the specified collection so that the specified index is valid.
*
* @param state the expression state
* @param elementType the type of the elements in the collection
* @param index the index into the collection that needs to be valid
* @param collection the collection to grow with elements
* @return true if collection growing succeeded, otherwise false
*/
@SuppressWarnings("unchecked")
private boolean growCollection(ExpressionState state, Class<?> elementType, int index,
Collection collection) {
if (state.getConfiguration().isAutoGrowCollections()) {
Object newCollectionElement = null;
try {
int newElements = index-collection.size();
if (elementType == null) {
throw new SpelEvaluationException(getStartPosition(), SpelMessage.UNABLE_TO_GROW_COLLECTION_UNKNOWN_ELEMENT_TYPE);
}
while (newElements>0) {
collection.add(elementType.newInstance());
newElements--;
}
newCollectionElement = elementType.newInstance();
}
catch (Exception ex) {
throw new SpelEvaluationException(getStartPosition(), ex, SpelMessage.UNABLE_TO_GROW_COLLECTION);
}
collection.add(newCollectionElement);
return true;
}
return false;
}
@Override
public String toStringAST() {
StringBuilder sb = new StringBuilder();