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Java JDBC 4.2 (JRE 8+) driver for YugaByte SQL database
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/*
* Copyright (c) 2004, PostgreSQL Global Development Group
* See the LICENSE file in the project root for more information.
*/
package org.postgresql.jdbc;
import static org.postgresql.util.internal.Nullness.castNonNull;
import org.postgresql.Driver;
import org.postgresql.core.BaseConnection;
import org.postgresql.core.BaseStatement;
import org.postgresql.core.CachedQuery;
import org.postgresql.core.Field;
import org.postgresql.core.ParameterList;
import org.postgresql.core.Provider;
import org.postgresql.core.Query;
import org.postgresql.core.QueryExecutor;
import org.postgresql.core.ResultCursor;
import org.postgresql.core.ResultHandlerBase;
import org.postgresql.core.SqlCommand;
import org.postgresql.core.Tuple;
import org.postgresql.util.GT;
import org.postgresql.util.PSQLException;
import org.postgresql.util.PSQLState;
import org.checkerframework.checker.index.qual.NonNegative;
import org.checkerframework.checker.lock.qual.GuardedBy;
import org.checkerframework.checker.nullness.qual.Nullable;
import org.checkerframework.checker.nullness.qual.RequiresNonNull;
import java.sql.Connection;
import java.sql.ResultSet;
import java.sql.SQLException;
import java.sql.SQLWarning;
import java.sql.Statement;
import java.util.ArrayList;
import java.util.List;
import java.util.TimeZone;
import java.util.TimerTask;
import java.util.concurrent.TimeUnit;
import java.util.concurrent.atomic.AtomicIntegerFieldUpdater;
import java.util.concurrent.atomic.AtomicReferenceFieldUpdater;
public class PgStatement implements Statement, BaseStatement {
private static final String[] NO_RETURNING_COLUMNS = new String[0];
/**
* Default state for use or not binary transfers. Can use only for testing purposes
*/
private static final boolean DEFAULT_FORCE_BINARY_TRANSFERS =
Boolean.getBoolean("org.postgresql.forceBinary");
// only for testing purposes. even single shot statements will use binary transfers
private boolean forceBinaryTransfers = DEFAULT_FORCE_BINARY_TRANSFERS;
protected final ResourceLock lock = new ResourceLock();
protected @Nullable ArrayList batchStatements;
protected @Nullable ArrayList<@Nullable ParameterList> batchParameters;
protected final int resultsettype; // the resultset type to return (ResultSet.TYPE_xxx)
protected final int concurrency; // is it updateable or not? (ResultSet.CONCUR_xxx)
private final int rsHoldability;
private boolean poolable;
private boolean closeOnCompletion;
protected int fetchdirection = ResultSet.FETCH_FORWARD;
// fetch direction hint (currently ignored)
/**
* Protects current statement from cancelTask starting, waiting for a bit, and waking up exactly
* on subsequent query execution. The idea is to atomically compare and swap the reference to the
* task, so the task can detect that statement executes different query than the one the
* cancelTask was created. Note: the field must be set/get/compareAndSet via
* {@link #CANCEL_TIMER_UPDATER} as per {@link AtomicReferenceFieldUpdater} javadoc.
*/
private volatile @Nullable TimerTask cancelTimerTask;
@SuppressWarnings("RedundantCast")
// Cast is needed for checkerframework to accept the code
private static final AtomicReferenceFieldUpdater CANCEL_TIMER_UPDATER =
AtomicReferenceFieldUpdater.newUpdater(
PgStatement.class, (Class<@Nullable TimerTask>) TimerTask.class, "cancelTimerTask");
/**
* Protects statement from out-of-order cancels. It protects from both
* {@link #setQueryTimeout(int)} and {@link #cancel()} induced ones.
*
* {@link #execute(String)} and friends change the field to
* {@link StatementCancelState#IN_QUERY} during execute. {@link #cancel()}
* ignores cancel request if state is {@link StatementCancelState#IDLE}.
* In case {@link #execute(String)} observes non-{@link StatementCancelState#IDLE} state as it
* completes the query, it waits till {@link StatementCancelState#CANCELLED}. Note: the field must be
* set/get/compareAndSet via {@link #STATE_UPDATER} as per {@link AtomicIntegerFieldUpdater}
* javadoc.
*/
private volatile StatementCancelState statementState = StatementCancelState.IDLE;
private static final AtomicReferenceFieldUpdater STATE_UPDATER =
AtomicReferenceFieldUpdater.newUpdater(PgStatement.class, StatementCancelState.class, "statementState");
/**
* Does the caller of execute/executeUpdate want generated keys for this execution? This is set by
* Statement methods that have generated keys arguments and cleared after execution is complete.
*/
protected boolean wantsGeneratedKeysOnce;
/**
* Was this PreparedStatement created to return generated keys for every execution? This is set at
* creation time and never cleared by execution.
*/
public boolean wantsGeneratedKeysAlways;
// The connection who created us
protected final PgConnection connection;
/**
* The warnings chain.
*/
protected volatile @Nullable PSQLWarningWrapper warnings;
/**
* Maximum number of rows to return, 0 = unlimited.
*/
protected int maxrows;
/**
* Number of rows to get in a batch.
*/
protected int fetchSize;
/**
* Timeout (in milliseconds) for a query.
*/
protected long timeout;
protected boolean replaceProcessingEnabled = true;
/**
* The current results.
*/
protected @Nullable ResultWrapper result;
/**
* The first unclosed result.
*/
protected @Nullable @GuardedBy("") ResultWrapper firstUnclosedResult;
/**
* Results returned by a statement that wants generated keys.
*/
protected @Nullable ResultWrapper generatedKeys;
protected int mPrepareThreshold; // Reuse threshold to enable use of PREPARE
protected int maxFieldSize;
protected boolean adaptiveFetch;
private @Nullable TimestampUtils timestampUtils; // our own Object because it's not thread safe
@SuppressWarnings("method.invocation")
PgStatement(PgConnection c, int rsType, int rsConcurrency, int rsHoldability)
throws SQLException {
this.connection = c;
forceBinaryTransfers |= c.getForceBinary();
resultsettype = rsType;
concurrency = rsConcurrency;
setFetchSize(c.getDefaultFetchSize());
setPrepareThreshold(c.getPrepareThreshold());
setAdaptiveFetch(c.getAdaptiveFetch());
this.rsHoldability = rsHoldability;
}
@Override
@SuppressWarnings("method.invocation")
public ResultSet createResultSet(@Nullable Query originalQuery, Field[] fields, List tuples,
@Nullable ResultCursor cursor) throws SQLException {
PgResultSet newResult = new PgResultSet(originalQuery, this, fields, tuples, cursor,
getMaxRows(), getMaxFieldSize(), getResultSetType(), getResultSetConcurrency(),
getResultSetHoldability(), getAdaptiveFetch());
newResult.setFetchSize(getFetchSize());
newResult.setFetchDirection(getFetchDirection());
return newResult;
}
public BaseConnection getPGConnection() {
return connection;
}
public @Nullable String getFetchingCursorName() {
return null;
}
@Override
public @NonNegative int getFetchSize() {
return fetchSize;
}
protected boolean wantsScrollableResultSet() {
return resultsettype != ResultSet.TYPE_FORWARD_ONLY;
}
protected boolean wantsHoldableResultSet() {
// FIXME: false if not supported
return rsHoldability == ResultSet.HOLD_CURSORS_OVER_COMMIT;
}
/**
* ResultHandler implementations for updates, queries, and either-or.
*/
public class StatementResultHandler extends ResultHandlerBase {
private @Nullable ResultWrapper results;
private @Nullable ResultWrapper lastResult;
@Nullable ResultWrapper getResults() {
return results;
}
private void append(ResultWrapper newResult) {
if (results == null) {
lastResult = results = newResult;
} else {
castNonNull(lastResult).append(newResult);
}
}
@Override
public void handleResultRows(Query fromQuery, Field[] fields, List tuples,
@Nullable ResultCursor cursor) {
try {
ResultSet rs = PgStatement.this.createResultSet(fromQuery, fields, tuples, cursor);
append(new ResultWrapper(rs));
} catch (SQLException e) {
handleError(e);
}
}
@Override
public void handleCommandStatus(String status, long updateCount, long insertOID) {
append(new ResultWrapper(updateCount, insertOID));
}
@Override
public void handleWarning(SQLWarning warning) {
PgStatement.this.addWarning(warning);
}
}
@Override
public ResultSet executeQuery(String sql) throws SQLException {
try (ResourceLock ignore = lock.obtain()) {
if (!executeWithFlags(sql, 0)) {
throw new PSQLException(GT.tr("No results were returned by the query."), PSQLState.NO_DATA);
}
return getSingleResultSet();
}
}
protected ResultSet getSingleResultSet() throws SQLException {
try (ResourceLock ignore = lock.obtain()) {
checkClosed();
ResultWrapper result = castNonNull(this.result);
if (result.getNext() != null) {
throw new PSQLException(GT.tr("Multiple ResultSets were returned by the query."),
PSQLState.TOO_MANY_RESULTS);
}
return castNonNull(result.getResultSet(), "result.getResultSet()");
}
}
@Override
public int executeUpdate(String sql) throws SQLException {
try (ResourceLock ignore = lock.obtain()) {
executeWithFlags(sql, QueryExecutor.QUERY_NO_RESULTS);
checkNoResultUpdate();
return getUpdateCount();
}
}
protected final void checkNoResultUpdate() throws SQLException {
try (ResourceLock ignore = lock.obtain()) {
checkClosed();
ResultWrapper iter = result;
while (iter != null) {
if (iter.getResultSet() != null) {
throw new PSQLException(GT.tr("A result was returned when none was expected."),
PSQLState.TOO_MANY_RESULTS);
}
iter = iter.getNext();
}
}
}
@Override
public boolean execute(String sql) throws SQLException {
return executeWithFlags(sql, 0);
}
@Override
public boolean executeWithFlags(String sql, int flags) throws SQLException {
return executeCachedSql(sql, flags, NO_RETURNING_COLUMNS);
}
private boolean executeCachedSql(String sql, int flags,
String @Nullable [] columnNames) throws SQLException {
PreferQueryMode preferQueryMode = connection.getPreferQueryMode();
// Simple statements should not replace ?, ? with $1, $2
boolean shouldUseParameterized = false;
QueryExecutor queryExecutor = connection.getQueryExecutor();
Object key = queryExecutor
.createQueryKey(sql, replaceProcessingEnabled, shouldUseParameterized, columnNames);
CachedQuery cachedQuery;
boolean shouldCache = preferQueryMode == PreferQueryMode.EXTENDED_CACHE_EVERYTHING;
if (shouldCache) {
cachedQuery = queryExecutor.borrowQueryByKey(key);
} else {
cachedQuery = queryExecutor.createQueryByKey(key);
}
if (wantsGeneratedKeysOnce) {
SqlCommand sqlCommand = cachedQuery.query.getSqlCommand();
wantsGeneratedKeysOnce = sqlCommand != null && sqlCommand.isReturningKeywordPresent();
}
boolean res;
try {
res = executeWithFlags(cachedQuery, flags);
} finally {
if (shouldCache) {
queryExecutor.releaseQuery(cachedQuery);
}
}
return res;
}
@Override
public boolean executeWithFlags(CachedQuery simpleQuery, int flags) throws SQLException {
checkClosed();
if (connection.getPreferQueryMode().compareTo(PreferQueryMode.EXTENDED) < 0) {
flags |= QueryExecutor.QUERY_EXECUTE_AS_SIMPLE;
}
execute(simpleQuery, null, flags);
try (ResourceLock ignore = lock.obtain()) {
checkClosed();
return result != null && result.getResultSet() != null;
}
}
@Override
public boolean executeWithFlags(int flags) throws SQLException {
checkClosed();
throw new PSQLException(GT.tr("Can''t use executeWithFlags(int) on a Statement."),
PSQLState.WRONG_OBJECT_TYPE);
}
/*
If there are multiple result sets we close any that have been processed and left open
by the client.
*/
private void closeUnclosedProcessedResults() throws SQLException {
try (ResourceLock ignore = lock.obtain()) {
ResultWrapper resultWrapper = this.firstUnclosedResult;
ResultWrapper currentResult = this.result;
for (; resultWrapper != currentResult && resultWrapper != null;
resultWrapper = resultWrapper.getNext()) {
PgResultSet rs = (PgResultSet) resultWrapper.getResultSet();
if (rs != null) {
rs.closeInternally();
}
}
firstUnclosedResult = resultWrapper;
}
}
protected void closeForNextExecution() throws SQLException {
// Every statement execution clears any previous warnings.
clearWarnings();
// Close any existing resultsets associated with this statement.
try (ResourceLock ignore = lock.obtain()) {
closeUnclosedProcessedResults();
if ( this.result != null && this.result.getResultSet() != null ) {
this.result.getResultSet().close();
}
result = null;
ResultWrapper generatedKeys = this.generatedKeys;
if (generatedKeys != null) {
ResultSet resultSet = generatedKeys.getResultSet();
if (resultSet != null) {
resultSet.close();
}
this.generatedKeys = null;
}
}
}
/**
* Returns true if query is unlikely to be reused.
*
* @param cachedQuery to check (null if current query)
* @return true if query is unlikely to be reused
*/
protected boolean isOneShotQuery(@Nullable CachedQuery cachedQuery) {
if (cachedQuery == null) {
return true;
}
cachedQuery.increaseExecuteCount();
return (mPrepareThreshold == 0 || cachedQuery.getExecuteCount() < mPrepareThreshold)
&& !getForceBinaryTransfer();
}
protected final void execute(CachedQuery cachedQuery,
@Nullable ParameterList queryParameters, int flags)
throws SQLException {
try (ResourceLock ignore = lock.obtain()) {
try {
executeInternal(cachedQuery, queryParameters, flags);
} catch (SQLException e) {
// Don't retry composite queries as it might get partially executed
if (cachedQuery.query.getSubqueries() != null
|| !connection.getQueryExecutor().willHealOnRetry(e)) {
throw e;
}
cachedQuery.query.close();
// Execute the query one more time
executeInternal(cachedQuery, queryParameters, flags);
}
}
}
private void executeInternal(CachedQuery cachedQuery,
@Nullable ParameterList queryParameters, int flags)
throws SQLException {
closeForNextExecution();
// Enable cursor-based resultset if possible.
if (fetchSize > 0 && !wantsScrollableResultSet() && !connection.getAutoCommit()
&& !wantsHoldableResultSet()) {
flags |= QueryExecutor.QUERY_FORWARD_CURSOR;
}
if (wantsGeneratedKeysOnce || wantsGeneratedKeysAlways) {
flags |= QueryExecutor.QUERY_BOTH_ROWS_AND_STATUS;
// If the no results flag is set (from executeUpdate)
// clear it so we get the generated keys results.
//
if ((flags & QueryExecutor.QUERY_NO_RESULTS) != 0) {
flags &= ~(QueryExecutor.QUERY_NO_RESULTS);
}
}
// Only use named statements after we hit the threshold. Note that only
// named statements can be transferred in binary format.
// isOneShotQuery will check to see if we have hit the prepareThreshold count
if (isOneShotQuery(cachedQuery)) {
flags |= QueryExecutor.QUERY_ONESHOT;
}
if (connection.getAutoCommit()) {
flags |= QueryExecutor.QUERY_SUPPRESS_BEGIN;
}
if (connection.hintReadOnly()) {
flags |= QueryExecutor.QUERY_READ_ONLY_HINT;
}
// updateable result sets do not yet support binary updates
if (concurrency != ResultSet.CONCUR_READ_ONLY) {
flags |= QueryExecutor.QUERY_NO_BINARY_TRANSFER;
}
Query queryToExecute = cachedQuery.query;
if (queryToExecute.isEmpty()) {
flags |= QueryExecutor.QUERY_SUPPRESS_BEGIN;
}
if (!queryToExecute.isStatementDescribed() && forceBinaryTransfers
&& (flags & QueryExecutor.QUERY_EXECUTE_AS_SIMPLE) == 0) {
// Simple 'Q' execution does not need to know parameter types
// When binaryTransfer is forced, then we need to know resulting parameter and column types,
// thus sending a describe request.
int flags2 = flags | QueryExecutor.QUERY_DESCRIBE_ONLY;
StatementResultHandler handler2 = new StatementResultHandler();
connection.getQueryExecutor().execute(queryToExecute, queryParameters, handler2, 0, 0,
flags2);
ResultWrapper result2 = handler2.getResults();
if (result2 != null) {
castNonNull(result2.getResultSet(), "result2.getResultSet()").close();
}
}
StatementResultHandler handler = new StatementResultHandler();
try (ResourceLock ignore = lock.obtain()) {
result = null;
}
try {
startTimer();
connection.getQueryExecutor().execute(queryToExecute, queryParameters, handler, maxrows,
fetchSize, flags, adaptiveFetch);
} finally {
killTimerTask();
}
try (ResourceLock ignore = lock.obtain()) {
checkClosed();
ResultWrapper currentResult = handler.getResults();
result = firstUnclosedResult = currentResult;
if (wantsGeneratedKeysOnce || wantsGeneratedKeysAlways) {
generatedKeys = currentResult;
result = castNonNull(currentResult, "handler.getResults()").getNext();
if (wantsGeneratedKeysOnce) {
wantsGeneratedKeysOnce = false;
}
}
}
}
@Override
public void setCursorName(String name) throws SQLException {
checkClosed();
// No-op.
}
private volatile int isClosed;
private static final AtomicIntegerFieldUpdater IS_CLOSED_UPDATER =
AtomicIntegerFieldUpdater.newUpdater(
PgStatement.class, "isClosed");
@Override
public int getUpdateCount() throws SQLException {
try (ResourceLock ignore = lock.obtain()) {
checkClosed();
if (result == null || result.getResultSet() != null) {
return -1;
}
long count = result.getUpdateCount();
return count > Integer.MAX_VALUE ? Statement.SUCCESS_NO_INFO : (int) count;
}
}
@Override
public boolean getMoreResults() throws SQLException {
return getMoreResults(CLOSE_ALL_RESULTS);
}
@Override
public int getMaxRows() throws SQLException {
checkClosed();
return maxrows;
}
@Override
public void setMaxRows(int max) throws SQLException {
checkClosed();
if (max < 0) {
throw new PSQLException(
GT.tr("Maximum number of rows must be a value greater than or equal to 0."),
PSQLState.INVALID_PARAMETER_VALUE);
}
maxrows = max;
}
@Override
public void setEscapeProcessing(boolean enable) throws SQLException {
checkClosed();
replaceProcessingEnabled = enable;
}
@Override
public int getQueryTimeout() throws SQLException {
checkClosed();
long seconds = timeout / 1000;
if (seconds >= Integer.MAX_VALUE) {
return Integer.MAX_VALUE;
}
return (int) seconds;
}
@Override
public void setQueryTimeout(int seconds) throws SQLException {
setQueryTimeoutMs(seconds * 1000L);
}
/**
* The queryTimeout limit is the number of milliseconds the driver will wait for a Statement to
* execute. If the limit is exceeded, a SQLException is thrown.
*
* @return the current query timeout limit in milliseconds; 0 = unlimited
* @throws SQLException if a database access error occurs
*/
public long getQueryTimeoutMs() throws SQLException {
checkClosed();
return timeout;
}
/**
* Sets the queryTimeout limit.
*
* @param millis - the new query timeout limit in milliseconds
* @throws SQLException if a database access error occurs
*/
public void setQueryTimeoutMs(long millis) throws SQLException {
checkClosed();
if (millis < 0) {
throw new PSQLException(GT.tr("Query timeout must be a value greater than or equals to 0."),
PSQLState.INVALID_PARAMETER_VALUE);
}
timeout = millis;
}
/**
* Either initializes new warning wrapper, or adds warning onto the chain.
*
* Although warnings are expected to be added sequentially, the warnings chain may be cleared
* concurrently at any time via {@link #clearWarnings()}, therefore it is possible that a warning
* added via this method is placed onto the end of the previous warning chain
*
* @param warn warning to add
*/
public void addWarning(SQLWarning warn) {
//copy reference to avoid NPE from concurrent modification of this.warnings
final PSQLWarningWrapper warnWrap = this.warnings;
if (warnWrap == null) {
this.warnings = new PSQLWarningWrapper(warn);
} else {
warnWrap.addWarning(warn);
}
}
@Override
public @Nullable SQLWarning getWarnings() throws SQLException {
checkClosed();
//copy reference to avoid NPE from concurrent modification of this.warnings
final PSQLWarningWrapper warnWrap = this.warnings;
return warnWrap != null ? warnWrap.getFirstWarning() : null;
}
@Override
public int getMaxFieldSize() throws SQLException {
return maxFieldSize;
}
@Override
public void setMaxFieldSize(int max) throws SQLException {
checkClosed();
if (max < 0) {
throw new PSQLException(
GT.tr("The maximum field size must be a value greater than or equal to 0."),
PSQLState.INVALID_PARAMETER_VALUE);
}
maxFieldSize = max;
}
/**
* Clears the warning chain.
* Note that while it is safe to clear warnings while the query is executing, warnings that are
* added between calls to {@link #getWarnings()} and #clearWarnings() may be missed.
* Therefore you should hold a reference to the tail of the previous warning chain
* and verify if its {@link SQLWarning#getNextWarning()} value is holds any new value.
*/
@Override
public void clearWarnings() throws SQLException {
warnings = null;
}
@Override
public @Nullable ResultSet getResultSet() throws SQLException {
try (ResourceLock ignore = lock.obtain()) {
checkClosed();
if (result == null) {
return null;
}
return result.getResultSet();
}
}
/**
* Note: even though {@code Statement} is automatically closed when it is garbage
* collected, it is better to close it explicitly to lower resource consumption.
*
* {@inheritDoc}
*/
@Override
public final void close() throws SQLException {
// closing an already closed Statement is a no-op.
if (!IS_CLOSED_UPDATER.compareAndSet(this, 0, 1)) {
return;
}
cancel();
closeForNextExecution();
closeImpl();
}
/**
* This is guaranteed to be called exactly once even in case of concurrent {@link #close()} calls.
* @throws SQLException in case of error
*/
protected void closeImpl() throws SQLException {
}
/*
*
* The following methods are postgres extensions and are defined in the interface BaseStatement
*
*/
@Override
public long getLastOID() throws SQLException {
try (ResourceLock ignore = lock.obtain()) {
checkClosed();
if (result == null) {
return 0;
}
return result.getInsertOID();
}
}
@Override
public void setPrepareThreshold(int newThreshold) throws SQLException {
checkClosed();
if (newThreshold < 0) {
forceBinaryTransfers = true;
newThreshold = 1;
}
this.mPrepareThreshold = newThreshold;
}
@Override
public int getPrepareThreshold() {
return mPrepareThreshold;
}
@Override
@SuppressWarnings("deprecation")
public void setUseServerPrepare(boolean flag) throws SQLException {
setPrepareThreshold(flag ? 1 : 0);
}
@Override
public boolean isUseServerPrepare() {
return false;
}
protected void checkClosed() throws SQLException {
if (isClosed()) {
throw new PSQLException(GT.tr("This statement has been closed."),
PSQLState.OBJECT_NOT_IN_STATE);
}
}
// ** JDBC 2 Extensions **
@Override
public void addBatch(String sql) throws SQLException {
checkClosed();
ArrayList batchStatements = this.batchStatements;
if (batchStatements == null) {
this.batchStatements = batchStatements = new ArrayList<>();
}
ArrayList<@Nullable ParameterList> batchParameters = this.batchParameters;
if (batchParameters == null) {
this.batchParameters = batchParameters = new ArrayList<@Nullable ParameterList>();
}
// Simple statements should not replace ?, ? with $1, $2
boolean shouldUseParameterized = false;
CachedQuery cachedQuery = connection.createQuery(sql, replaceProcessingEnabled, shouldUseParameterized);
batchStatements.add(cachedQuery.query);
batchParameters.add(null);
}
@Override
public void clearBatch() throws SQLException {
if (batchStatements != null) {
batchStatements.clear();
}
if (batchParameters != null) {
batchParameters.clear();
}
}
protected BatchResultHandler createBatchHandler(Query[] queries,
@Nullable ParameterList[] parameterLists) {
return new BatchResultHandler(this, queries, parameterLists,
wantsGeneratedKeysAlways);
}
@RequiresNonNull({"batchStatements", "batchParameters"})
private BatchResultHandler internalExecuteBatch() throws SQLException {
// Construct query/parameter arrays.
transformQueriesAndParameters();
ArrayList batchStatements = castNonNull(this.batchStatements);
ArrayList<@Nullable ParameterList> batchParameters = castNonNull(this.batchParameters);
// Empty arrays should be passed to toArray
// see http://shipilev.net/blog/2016/arrays-wisdom-ancients/
Query[] queries = batchStatements.toArray(new Query[0]);
@Nullable ParameterList[] parameterLists = batchParameters.toArray(new ParameterList[0]);
batchStatements.clear();
batchParameters.clear();
int flags;
// Force a Describe before any execution? We need to do this if we're going
// to send anything dependent on the Describe results, e.g. binary parameters.
boolean preDescribe = false;
if (wantsGeneratedKeysAlways) {
/*
* This batch will return generated keys, tell the executor to expect result rows. We also
* force a Describe later so we know the size of the results to expect.
*
* If the parameter type(s) change between batch entries and the default binary-mode changes
* we might get mixed binary and text in a single result set column, which we cannot handle.
* To prevent this, disable binary transfer mode in batches that return generated keys. See
* GitHub issue #267
*/
flags = QueryExecutor.QUERY_BOTH_ROWS_AND_STATUS | QueryExecutor.QUERY_NO_BINARY_TRANSFER;
} else {
// If a batch hasn't specified that it wants generated keys, using the appropriate
// Connection.createStatement(...) interfaces, disallow any result set.
flags = QueryExecutor.QUERY_NO_RESULTS;
}
PreferQueryMode preferQueryMode = connection.getPreferQueryMode();
if (preferQueryMode == PreferQueryMode.SIMPLE
|| (preferQueryMode == PreferQueryMode.EXTENDED_FOR_PREPARED
&& parameterLists[0] == null)) {
flags |= QueryExecutor.QUERY_EXECUTE_AS_SIMPLE;
}
boolean sameQueryAhead = queries.length > 1 && queries[0] == queries[1];
if (!sameQueryAhead
// If executing the same query twice in a batch, make sure the statement
// is server-prepared. In other words, "oneshot" only if the query is one in the batch
// or the queries are different
|| isOneShotQuery(null)) {
flags |= QueryExecutor.QUERY_ONESHOT;
} else {
// If a batch requests generated keys and isn't already described,
// force a Describe of the query before proceeding. That way we can
// determine the appropriate size of each batch by estimating the
// maximum data returned. Without that, we don't know how many queries
// we'll be able to queue up before we risk a deadlock.
// (see v3.QueryExecutorImpl's MAX_BUFFERED_RECV_BYTES)
// SameQueryAhead is just a quick way to issue pre-describe for batch execution
// TODO: It should be reworked into "pre-describe if query has unknown parameter
// types and same query is ahead".
preDescribe = (wantsGeneratedKeysAlways || sameQueryAhead)
&& !queries[0].isStatementDescribed();
/*
* It's also necessary to force a Describe on the first execution of the new statement, even
* though we already described it, to work around bug #267.
*/
flags |= QueryExecutor.QUERY_FORCE_DESCRIBE_PORTAL;
}
if (connection.getAutoCommit()) {
flags |= QueryExecutor.QUERY_SUPPRESS_BEGIN;
}
if (connection.hintReadOnly()) {
flags |= QueryExecutor.QUERY_READ_ONLY_HINT;
}
BatchResultHandler handler;
handler = createBatchHandler(queries, parameterLists);
if ((preDescribe || forceBinaryTransfers)
&& (flags & QueryExecutor.QUERY_EXECUTE_AS_SIMPLE) == 0) {
// Do a client-server round trip, parsing and describing the query so we
// can determine its result types for use in binary parameters, batch sizing,
// etc.
int flags2 = flags | QueryExecutor.QUERY_DESCRIBE_ONLY;
StatementResultHandler handler2 = new StatementResultHandler();
try {
connection.getQueryExecutor().execute(queries[0], parameterLists[0], handler2, 0, 0, flags2);
} catch (SQLException e) {
// Unable to parse the first statement -> throw BatchUpdateException
handler.handleError(e);
handler.handleCompletion();
// Will not reach here (see above)
}
ResultWrapper result2 = handler2.getResults();
if (result2 != null) {
castNonNull(result2.getResultSet(), "result2.getResultSet()").close();
}
}
try (ResourceLock ignore = lock.obtain()) {
result = null;
}
try {
startTimer();
connection.getQueryExecutor().execute(queries, parameterLists, handler, maxrows, fetchSize,
flags, adaptiveFetch);
} finally {
killTimerTask();
// There might be some rows generated even in case of failures
try (ResourceLock ignore = lock.obtain()) {
checkClosed();
if (wantsGeneratedKeysAlways) {
generatedKeys = new ResultWrapper(handler.getGeneratedKeys());
}
}
}
return handler;
}
@Override
public int[] executeBatch() throws SQLException {
checkClosed();
closeForNextExecution();
if (batchStatements == null || batchStatements.isEmpty() || batchParameters == null) {
return new int[0];
}
return internalExecuteBatch().getUpdateCount();
}
@Override
public void cancel() throws SQLException {
if (statementState == StatementCancelState.IDLE) {
return;
}
if (!STATE_UPDATER.compareAndSet(this, StatementCancelState.IN_QUERY,
StatementCancelState.CANCELING)) {
// Not in query, there's nothing to cancel
return;
}
// Use connection lock to avoid spinning in killTimerTask
try (ResourceLock connectionLock = connection.obtainLock()) {
try {
connection.cancelQuery();
} finally {
STATE_UPDATER.set(this, StatementCancelState.CANCELLED);
connection.lockCondition().signalAll(); // wake-up killTimerTask
}
}
}
@Override
public Connection getConnection() throws SQLException {
return connection;
}
@Override
public int getFetchDirection() {
return fetchdirection;
}
@Override
public int getResultSetConcurrency() {
return concurrency;
}
@Override
public int getResultSetType() {
return resultsettype;
}
@Override
public void setFetchDirection(int direction) throws SQLException {
switch (direction) {
case ResultSet.FETCH_FORWARD:
case ResultSet.FETCH_REVERSE:
case ResultSet.FETCH_UNKNOWN:
fetchdirection = direction;
break;
default:
throw new PSQLException(GT.tr("Invalid fetch direction constant: {0}.", direction),
PSQLState.INVALID_PARAMETER_VALUE);
}
}
@Override
public void setFetchSize(@NonNegative int rows) throws SQLException {
checkClosed();
if (rows < 0) {
throw new PSQLException(GT.tr("Fetch size must be a value greater to or equal to 0."),
PSQLState.INVALID_PARAMETER_VALUE);
}
fetchSize = rows;
}
private void startTimer() {
/*
* there shouldn't be any previous timer active, but better safe than sorry.
*/
cleanupTimer();
STATE_UPDATER.set(this, StatementCancelState.IN_QUERY);
if (timeout == 0) {
return;
}
TimerTask cancelTask = new StatementCancelTimerTask(this);
CANCEL_TIMER_UPDATER.set(this, cancelTask);
connection.addTimerTask(cancelTask, timeout);
}
void cancelIfStillNeeded(TimerTask timerTask) {
try {
if (!CANCEL_TIMER_UPDATER.compareAndSet(this, timerTask, null)) {
// Nothing to do here, statement has already finished and cleared
// cancelTimerTask reference
return;
}
cancel();
} catch (SQLException e) {
}
}
/**
* Clears {@link #cancelTimerTask} if any. Returns true if and only if "cancel" timer task would
* never invoke {@link #cancel()}.
*/
private boolean cleanupTimer() {
TimerTask timerTask = CANCEL_TIMER_UPDATER.get(this);
if (timerTask == null) {
// If timeout is zero, then timer task did not exist, so we safely report "all clear"
return timeout == 0;
}
if (!CANCEL_TIMER_UPDATER.compareAndSet(this, timerTask, null)) {
// Failed to update reference -> timer has just fired, so we must wait for the query state to
// become "cancelling".
return false;
}
timerTask.cancel();
connection.purgeTimerTasks();
// All clear
return true;
}
private void killTimerTask() {
boolean timerTaskIsClear = cleanupTimer();
// The order is important here: in case we need to wait for the cancel task, the state must be
// kept StatementCancelState.IN_QUERY, so cancelTask would be able to cancel the query.
// It is believed that this case is very rare, so "additional cancel and wait below" would not
// harm it.
if (timerTaskIsClear && STATE_UPDATER.compareAndSet(this, StatementCancelState.IN_QUERY, StatementCancelState.IDLE)) {
return;
}
// Being here means someone managed to call .cancel() and our connection did not receive
// "timeout error"
// We wait till state becomes "cancelled"
boolean interrupted = false;
try (ResourceLock connectionLock = connection.obtainLock()) {
// state check is performed with connection lock so it detects "cancelled" state faster
// In other words, it prevents unnecessary ".wait()" call
while (!STATE_UPDATER.compareAndSet(this, StatementCancelState.CANCELLED, StatementCancelState.IDLE)) {
try {
// Note: wait timeout here is irrelevant since connection.obtainLock() would block until
// .cancel finishes
connection.lockCondition().await(10, TimeUnit.MILLISECONDS);
} catch (InterruptedException e) { // NOSONAR
// Either re-interrupt this method or rethrow the "InterruptedException"
interrupted = true;
}
}
}
if (interrupted) {
Thread.currentThread().interrupt();
}
}
protected boolean getForceBinaryTransfer() {
return forceBinaryTransfers;
}
@Override
public long getLargeUpdateCount() throws SQLException {
try (ResourceLock ignore = lock.obtain()) {
checkClosed();
if (result == null || result.getResultSet() != null) {
return -1;
}
return result.getUpdateCount();
}
}
@Override
public void setLargeMaxRows(long max) throws SQLException {
throw Driver.notImplemented(this.getClass(), "setLargeMaxRows");
}
@Override
public long getLargeMaxRows() throws SQLException {
throw Driver.notImplemented(this.getClass(), "getLargeMaxRows");
}
@Override
public long[] executeLargeBatch() throws SQLException {
checkClosed();
closeForNextExecution();
if (batchStatements == null || batchStatements.isEmpty() || batchParameters == null) {
return new long[0];
}
return internalExecuteBatch().getLargeUpdateCount();
}
@Override
public long executeLargeUpdate(String sql) throws SQLException {
try (ResourceLock ignore = lock.obtain()) {
executeWithFlags(sql, QueryExecutor.QUERY_NO_RESULTS);
checkNoResultUpdate();
return getLargeUpdateCount();
}
}
@Override
public long executeLargeUpdate(String sql, int autoGeneratedKeys) throws SQLException {
if (autoGeneratedKeys == Statement.NO_GENERATED_KEYS) {
return executeLargeUpdate(sql);
}
return executeLargeUpdate(sql, (String[]) null);
}
@Override
public long executeLargeUpdate(String sql, int[] columnIndexes) throws SQLException {
if (columnIndexes == null || columnIndexes.length == 0) {
return executeLargeUpdate(sql);
}
throw new PSQLException(GT.tr("Returning autogenerated keys by column index is not supported."),
PSQLState.NOT_IMPLEMENTED);
}
@Override
public long executeLargeUpdate(String sql, String @Nullable [] columnNames) throws SQLException {
try (ResourceLock ignore = lock.obtain()) {
if (columnNames != null && columnNames.length == 0) {
return executeLargeUpdate(sql);
}
wantsGeneratedKeysOnce = true;
if (!executeCachedSql(sql, 0, columnNames)) {
// no resultset returned. What's a pity!
}
return getLargeUpdateCount();
}
}
@Override
public boolean isClosed() throws SQLException {
return isClosed == 1;
}
@Override
public void setPoolable(boolean poolable) throws SQLException {
checkClosed();
this.poolable = poolable;
}
@Override
public boolean isPoolable() throws SQLException {
checkClosed();
return poolable;
}
@Override
public boolean isWrapperFor(Class> iface) throws SQLException {
return iface.isAssignableFrom(getClass());
}
@Override
public T unwrap(Class iface) throws SQLException {
if (iface.isAssignableFrom(getClass())) {
return iface.cast(this);
}
throw new SQLException("Cannot unwrap to " + iface.getName());
}
@Override
public void closeOnCompletion() throws SQLException {
closeOnCompletion = true;
}
@Override
public boolean isCloseOnCompletion() throws SQLException {
return closeOnCompletion;
}
protected void checkCompletion() throws SQLException {
if (!closeOnCompletion) {
return;
}
try (ResourceLock ignore = lock.obtain()) {
ResultWrapper result = firstUnclosedResult;
while (result != null) {
ResultSet resultSet = result.getResultSet();
if (resultSet != null && !resultSet.isClosed()) {
return;
}
result = result.getNext();
}
}
// prevent all ResultSet.close arising from Statement.close to loop here
closeOnCompletion = false;
try {
close();
} finally {
// restore the status if one rely on isCloseOnCompletion
closeOnCompletion = true;
}
}
@Override
public boolean getMoreResults(int current) throws SQLException {
try (ResourceLock ignore = lock.obtain()) {
checkClosed();
// CLOSE_CURRENT_RESULT
if (current == Statement.CLOSE_CURRENT_RESULT && result != null
&& result.getResultSet() != null) {
result.getResultSet().close();
}
// Advance resultset.
if (result != null) {
result = result.getNext();
}
// CLOSE_ALL_RESULTS
if (current == Statement.CLOSE_ALL_RESULTS) {
// Close preceding resultsets.
closeUnclosedProcessedResults();
}
// Done.
return result != null && result.getResultSet() != null;
}
}
@Override
public ResultSet getGeneratedKeys() throws SQLException {
try (ResourceLock ignore = lock.obtain()) {
checkClosed();
if (generatedKeys == null || generatedKeys.getResultSet() == null) {
return createDriverResultSet(new Field[0], new ArrayList<>());
}
return generatedKeys.getResultSet();
}
}
@Override
public int executeUpdate(String sql, int autoGeneratedKeys) throws SQLException {
if (autoGeneratedKeys == Statement.NO_GENERATED_KEYS) {
return executeUpdate(sql);
}
return executeUpdate(sql, (String[]) null);
}
@Override
public int executeUpdate(String sql, int[] columnIndexes) throws SQLException {
if (columnIndexes == null || columnIndexes.length == 0) {
return executeUpdate(sql);
}
throw new PSQLException(GT.tr("Returning autogenerated keys by column index is not supported."),
PSQLState.NOT_IMPLEMENTED);
}
@Override
public int executeUpdate(String sql, String @Nullable [] columnNames) throws SQLException {
try (ResourceLock ignore = lock.obtain()) {
if (columnNames != null && columnNames.length == 0) {
return executeUpdate(sql);
}
wantsGeneratedKeysOnce = true;
if (!executeCachedSql(sql, 0, columnNames)) {
// no resultset returned. What's a pity!
}
return getUpdateCount();
}
}
@Override
public boolean execute(String sql, int autoGeneratedKeys) throws SQLException {
if (autoGeneratedKeys == Statement.NO_GENERATED_KEYS) {
return execute(sql);
}
return execute(sql, (String[]) null);
}
@Override
public boolean execute(String sql, int @Nullable [] columnIndexes) throws SQLException {
if (columnIndexes != null && columnIndexes.length == 0) {
return execute(sql);
}
throw new PSQLException(GT.tr("Returning autogenerated keys by column index is not supported."),
PSQLState.NOT_IMPLEMENTED);
}
@Override
public boolean execute(String sql, String @Nullable [] columnNames) throws SQLException {
try (ResourceLock ignore = lock.obtain()) {
if (columnNames != null && columnNames.length == 0) {
return execute(sql);
}
wantsGeneratedKeysOnce = true;
return executeCachedSql(sql, 0, columnNames);
}
}
@Override
public int getResultSetHoldability() throws SQLException {
return rsHoldability;
}
@Override
public ResultSet createDriverResultSet(Field[] fields, List tuples)
throws SQLException {
return createResultSet(null, fields, tuples, null);
}
protected void transformQueriesAndParameters() throws SQLException {
}
@Override
public void setAdaptiveFetch(boolean adaptiveFetch) {
this.adaptiveFetch = adaptiveFetch;
}
@Override
public boolean getAdaptiveFetch() {
return adaptiveFetch;
}
protected TimestampUtils getTimestampUtils() {
if (timestampUtils == null) {
timestampUtils = new TimestampUtils(!connection.getQueryExecutor().getIntegerDateTimes(), (Provider) new QueryExecutorTimeZoneProvider(connection.getQueryExecutor()));
}
return timestampUtils;
}
}
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