package io.ebeaninternal.server.persist;
import io.ebeaninternal.api.SpiTransaction;
import io.ebeaninternal.server.core.PersistRequest;
import io.ebeaninternal.server.core.PersistRequestBean;
import io.ebeaninternal.server.deploy.BeanDescriptor;
import java.util.ArrayList;
import java.util.Arrays;
import java.util.HashMap;
/**
* Controls the batch ordering of persist requests.
* <p>
* Persist requests include bean inserts updates deletes and UpdateSql and
* CallableSql requests.
* </p>
* <p>
* This object queues up the requests into appropriate entries according to the
* 'depth' and the 'type' of the requests. The depth relates to how saves and
* deletes cascade following the associations of a bean. For saving Associated
* One cascades reduce the depth (-1) and associated many's increase the depth.
* The initial depth of a request is 0.
* </p>
*/
public final class BatchControl {
/**
* Used to sort queue entries by depth.
*/
private static final BatchDepthComparator depthComparator = new BatchDepthComparator();
/**
* Controls batching of the PreparedStatements. This should be flushed after
* each 'depth'.
*/
private final BatchedPstmtHolder pstmtHolder = new BatchedPstmtHolder();
/**
* Map of the BatchedBeanHolder objects. They each have a depth and are later
* sorted by their depth to get the execution order.
*/
private final HashMap<String, BatchedBeanHolder> beanHoldMap = new HashMap<>();
private final SpiTransaction transaction;
/**
* The size at which the batch queue will flush. This should be close to the
* number of statements that are batched into a single PreparedStatement. This
* size relates to the size of a list in a BatchQueueEntry and not the total
* number of request which could be more than that.
*/
private int batchSize;
/**
* If true try to get generated keys from inserts.
*/
private boolean getGeneratedKeys;
private boolean batchFlushOnMixed = true;
/**
* Create for a given transaction, PersistExecute, default size and getGeneratedKeys.
*/
public BatchControl(SpiTransaction t, int batchSize, boolean getGenKeys) {
this.transaction = t;
this.batchSize = batchSize;
this.getGeneratedKeys = getGenKeys;
transaction.setBatchControl(this);
}
/**
* Set this flag to false to allow batching of a mix of Beans and UpdateSql
* (or CallableSql). Normally if you mix the two this will result in an
* automatic flush.
* <p>
* Note that UpdateSql and CallableSql will ALWAYS flush first. This is due to
* it already having been bound to a PreparedStatement where as the Beans go
* through a 2 step process when they are flushed (delayed binding).
* </p>
*/
public void setBatchFlushOnMixed(boolean flushBatchOnMixed) {
this.batchFlushOnMixed = flushBatchOnMixed;
}
/**
* Return the batchSize.
*/
public int getBatchSize() {
return batchSize;
}
/**
* Set the size of batch execution.
* <p>
* The user can set this via the Transaction.
* </p>
*/
public void setBatchSize(int batchSize) {
if (batchSize > 1) {
this.batchSize = batchSize;
}
}
/**
* Set whether or not to use getGeneratedKeys for this batch execution.
* <p>
* The user can set this via the transaction
* </p>
*/
public void setGetGeneratedKeys(Boolean getGeneratedKeys) {
if (getGeneratedKeys != null) {
this.getGeneratedKeys = getGeneratedKeys;
}
}
/**
* Execute a Orm Update, SqlUpdate or CallableSql.
* <p>
* These all go straight to jdbc and use addBatch(). Entity beans goto a queue
* and wait there so that the jdbc is executed in the correct order according
* to the depth.
* </p>
*/
public int executeStatementOrBatch(PersistRequest request, boolean batch) throws BatchedSqlException {
if (!batch || (batchFlushOnMixed && !isBeansEmpty())) {
// flush when mixing beans and updateSql
flush();
}
if (!batch) {
// execute the request immediately without batching
return request.executeNow();
}
if (pstmtHolder.getMaxSize() >= batchSize) {
flush();
}
// for OrmUpdate, SqlUpdate, CallableSql there is no queue...
// so straight to jdbc prepared statement and use addBatch().
// aka executeNow() may use addBatch().
request.executeNow();
return -1;
}
/**
* Entity Bean insert, update or delete. This will either execute the request
* immediately or queue it for batch processing later. The queue is flushedIntercept
* according to the depth (object graph depth).
*/
public int executeOrQueue(PersistRequestBean<?> request, boolean batch) throws BatchedSqlException {
if (!batch || (batchFlushOnMixed && !pstmtHolder.isEmpty())) {
// flush when mixing beans and updateSql
flush();
}
if (!batch) {
return request.executeNow();
}
if (addToBatch(request)) {
// flush as the top level has hit the batch size
flush();
}
return -1;
}
/**
* Add the request to the batch and return true if we should flush.
*/
private boolean addToBatch(PersistRequestBean<?> request) throws BatchedSqlException {
BatchedBeanHolder beanHolder = getBeanHolder(request);
int bufferSize = beanHolder.append(request);
// return true if top level has hit batch size
return bufferSize == batchSize && beanHolder.getOrder() == 100;
}
/**
* Return the actual batch of PreparedStatements.
*/
public BatchedPstmtHolder getPstmtHolder() {
return pstmtHolder;
}
/**
* Return true if the queue is empty.
*/
public boolean isEmpty() {
return (isBeansEmpty() && pstmtHolder.isEmpty());
}
/**
* Flush any batched PreparedStatements.
*/
protected void flushPstmtHolder() throws BatchedSqlException {
pstmtHolder.flush(getGeneratedKeys);
}
/**
* Execute all the requests contained in the list.
*/
protected void executeNow(ArrayList<PersistRequest> list) throws BatchedSqlException {
for (int i = 0; i < list.size(); i++) {
if (i % batchSize == 0) {
// hit the batch size so flush
flushPstmtHolder();
}
list.get(i).executeNow();
}
flushPstmtHolder();
}
/**
* Flush without resetting the topOrder (maintains the depth info).
*/
public void flush() throws BatchedSqlException {
flush(false);
}
/**
* Flush with a reset the topOrder (fully empty the batch).
*/
public void flushReset() throws BatchedSqlException {
flush(true);
}
/**
* Clears the batch, discarding all batched statements.
*/
public void clear() {
pstmtHolder.clear();
beanHoldMap.clear();
}
/**
* execute all the requests currently queued or batched.
*/
private void flush(boolean resetTop) throws BatchedSqlException {
try {
if (!pstmtHolder.isEmpty()) {
// Flush existing pstmts (updateSql or callableSql)
flushPstmtHolder();
}
if (isEmpty()) {
// Nothing in queue to flush
return;
}
// convert entry map to array for sorting
BatchedBeanHolder[] bsArray = getBeanHolderArray();
// sort the entries by depth
Arrays.sort(bsArray, depthComparator);
if (transaction.isLogSummary()) {
transaction.logSummary("BatchControl flush " + Arrays.toString(bsArray));
}
for (BatchedBeanHolder aBsArray : bsArray) {
aBsArray.executeNow();
}
if (resetTop) {
beanHoldMap.clear();
}
} catch (BatchedSqlException e) {
// clear the batch on error in case we want to
// catch, rollback and continue processing
clear();
throw e;
}
}
/**
* Return an entry for the given type description. The type description is
* typically the bean class name (or table name for MapBeans).
*/
private BatchedBeanHolder getBeanHolder(PersistRequestBean<?> request) throws BatchedSqlException {
BeanDescriptor<?> beanDescriptor = request.getBeanDescriptor();
BatchedBeanHolder batchBeanHolder = beanHoldMap.get(beanDescriptor.getFullName());
if (batchBeanHolder == null) {
int relativeDepth = transaction.depth();
if (relativeDepth == 0 && !beanHoldMap.isEmpty()) {
// flush and reset the batch as we are changing the type of our top level
// bean so just keep it simple and flush and reset the top
flushReset();
}
batchBeanHolder = new BatchedBeanHolder(this, beanDescriptor, 100 + relativeDepth);
beanHoldMap.put(beanDescriptor.getFullName(), batchBeanHolder);
}
return batchBeanHolder;
}
/**
* Return true if this holds no persist requests.
*/
private boolean isBeansEmpty() {
if (beanHoldMap.isEmpty()) {
return true;
}
for (BatchedBeanHolder beanHolder : beanHoldMap.values()) {
if (!beanHolder.isEmpty()) {
return false;
}
}
return true;
}
/**
* Return the BatchedBeanHolder's ready for sorting and executing.
*/
private BatchedBeanHolder[] getBeanHolderArray() {
return beanHoldMap.values().toArray(new BatchedBeanHolder[beanHoldMap.size()]);
}
}