org.verdictdb.jdbc41.VerdictStatement Maven / Gradle / Ivy
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/*
* Copyright 2018 University of Michigan
*
* 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 org.verdictdb.jdbc41;
import java.sql.Connection;
import java.sql.ResultSet;
import java.sql.SQLException;
import java.sql.SQLFeatureNotSupportedException;
import java.sql.SQLWarning;
import org.verdictdb.VerdictContext;
import org.verdictdb.VerdictResultStream;
import org.verdictdb.VerdictSingleResult;
import org.verdictdb.commons.VerdictDBLogger;
import org.verdictdb.coordinator.ExecutionContext;
import org.verdictdb.exception.VerdictDBException;
public class VerdictStatement implements java.sql.Statement {
Connection conn;
ExecutionContext executionContext;
VerdictSingleResult result;
private VerdictDBLogger log = VerdictDBLogger.getLogger(this.getClass());
public VerdictStatement(Connection conn, VerdictContext context) {
this.conn = conn;
this.executionContext = context.createNewExecutionContext();
}
/**
* Created by Shucheng Zhong on 9/13/18
*
* It will try to get the VerdictSingleResult from VerdictResultStream
* and append the VerdictSingleResult to VerdictStreamResultSet
* until all the VerdictSingleResults have return.
* Since it running on separate thread, it won't block user querying from
* the ResultSet
*/
class ExecuteStream implements Runnable {
VerdictResultStream resultStream;
VerdictStreamResultSet resultSet;
ExecutionContext executionContext;
ExecuteStream(VerdictResultStream resultStream, VerdictStreamResultSet resultSet, ExecutionContext executionContext) {
this.resultStream = resultStream;
this.resultSet = resultSet;
this.executionContext = executionContext;
}
/**
* When the last SingleResult is returned, it will synchronized the hasReadAllQueryResults flag of VerdictStreamResultSet
* to block possible call of next(). It will set status of VerdictStreamResultSet to be complete and
* append the last SingleResult to VerdictStreamResultSet.
*/
public void run() {
while (!resultStream.isCompleted()) {
while (resultStream.hasNext()) {
VerdictSingleResult singleResult = resultStream.next();
if (!resultStream.hasNext()) {
// Must have synchronized keyword. Need to make sure the block is atomic because VerdictStreamResultSet.next() also use hasReadAllQueryResults flag.
// Otherwise, VerdictStreamResultSet may be unware the processing is completed after the last singleResult is appended.
synchronized ((Object) resultSet.hasReadAllQueryResults) {
resultSet.appendSingleResult(singleResult);
resultSet.setCompleted();
}
log.debug("Execution Completed\n");
} else {
resultSet.appendSingleResult(singleResult);
}
}
}
}
public void abort() {
executionContext.abort();
}
}
private Boolean checkStreamQuery(String query) {
if (query.trim().toLowerCase().startsWith("stream")) {
return true;
}
return false;
}
@Override
public boolean execute(String sql) throws SQLException {
try {
result = executionContext.sql(sql, false);
if (result == null) {
return false;
}
return !result.isEmpty();
} catch (VerdictDBException e) {
throw new SQLException(e);
}
}
@Override
public ResultSet executeQuery(String sql) throws SQLException {
try {
if (checkStreamQuery(sql)) {
VerdictStreamResultSet resultSet = new VerdictStreamResultSet();
sql = sql.replaceFirst("(?i)stream", "");
VerdictResultStream resultStream = executionContext.streamsql(sql);
ExecuteStream executeStream = new ExecuteStream(resultStream, resultSet, executionContext);
resultSet.setRunnable(executeStream);
new Thread(executeStream).start();
return resultSet;
}
result = executionContext.sql(sql);
return new VerdictResultSet(result);
} catch (VerdictDBException e) {
throw new SQLException(e);
}
}
@Override
public int executeUpdate(String sql) throws SQLException {
try {
result = executionContext.sql(sql);
return (int) result.getRowCount();
} catch (VerdictDBException e) {
throw new SQLException(e);
}
}
@Override
public void close() throws SQLException {
// dongyoungy: is this correct for close() to also call terminate() just like cancel()?
executionContext.terminate();
}
@Override
public boolean isClosed() throws SQLException {
// TODO Auto-generated method stub
return false;
}
@Override
public ResultSet getResultSet() throws SQLException {
return new VerdictResultSet(result);
}
@Override
public java.sql.Connection getConnection() throws SQLException {
return conn;
}
@Override
public T unwrap(Class iface) throws SQLException {
throw new SQLFeatureNotSupportedException();
}
@Override
public boolean isWrapperFor(Class iface) throws SQLException {
throw new SQLFeatureNotSupportedException();
}
@Override
public int getMaxFieldSize() throws SQLException {
return 0; // no limit
}
@Override
public void setMaxFieldSize(int max) throws SQLException {
throw new SQLFeatureNotSupportedException();
}
@Override
public int getMaxRows() throws SQLException {
return 0; // no limit
}
@Override
public void setMaxRows(int max) throws SQLException {
throw new SQLFeatureNotSupportedException();
}
@Override
public void setEscapeProcessing(boolean enable) throws SQLException {
throw new SQLFeatureNotSupportedException();
}
@Override
public int getQueryTimeout() throws SQLException {
throw new SQLFeatureNotSupportedException();
}
@Override
public void setQueryTimeout(int seconds) throws SQLException {
throw new SQLFeatureNotSupportedException();
}
@Override
public void cancel() throws SQLException {
executionContext.terminate();
}
@Override
public SQLWarning getWarnings() throws SQLException {
return null;
}
@Override
public void clearWarnings() throws SQLException {
}
@Override
public void setCursorName(String name) throws SQLException {
throw new SQLFeatureNotSupportedException();
}
@Override
public int getUpdateCount() throws SQLException {
return 0;
}
@Override
public boolean getMoreResults() throws SQLException {
return false;
}
@Override
public void setFetchDirection(int direction) throws SQLException {
throw new SQLFeatureNotSupportedException();
}
@Override
public int getFetchDirection() throws SQLException {
throw new SQLFeatureNotSupportedException();
}
@Override
public void setFetchSize(int rows) throws SQLException {
throw new SQLFeatureNotSupportedException();
}
@Override
public int getFetchSize() throws SQLException {
throw new SQLFeatureNotSupportedException();
}
@Override
public int getResultSetConcurrency() throws SQLException {
throw new SQLFeatureNotSupportedException();
}
@Override
public int getResultSetType() throws SQLException {
throw new SQLFeatureNotSupportedException();
}
@Override
public void addBatch(String sql) throws SQLException {
throw new SQLFeatureNotSupportedException();
}
@Override
public void clearBatch() throws SQLException {
throw new SQLFeatureNotSupportedException();
}
@Override
public int[] executeBatch() throws SQLException {
throw new SQLFeatureNotSupportedException();
}
@Override
public boolean getMoreResults(int current) throws SQLException {
throw new SQLFeatureNotSupportedException();
}
@Override
public ResultSet getGeneratedKeys() throws SQLException {
throw new SQLFeatureNotSupportedException();
}
@Override
public int executeUpdate(String sql, int autoGeneratedKeys) throws SQLException {
throw new SQLFeatureNotSupportedException();
}
@Override
public int executeUpdate(String sql, int[] columnIndexes) throws SQLException {
throw new SQLFeatureNotSupportedException();
}
@Override
public int executeUpdate(String sql, String[] columnNames) throws SQLException {
throw new SQLFeatureNotSupportedException();
}
@Override
public boolean execute(String sql, int autoGeneratedKeys) throws SQLException {
throw new SQLFeatureNotSupportedException();
}
@Override
public boolean execute(String sql, int[] columnIndexes) throws SQLException {
throw new SQLFeatureNotSupportedException();
}
@Override
public boolean execute(String sql, String[] columnNames) throws SQLException {
throw new SQLFeatureNotSupportedException();
}
@Override
public int getResultSetHoldability() throws SQLException {
throw new SQLFeatureNotSupportedException();
}
@Override
public void setPoolable(boolean poolable) throws SQLException {
throw new SQLFeatureNotSupportedException();
}
@Override
public boolean isPoolable() throws SQLException {
throw new SQLFeatureNotSupportedException();
}
@Override
public void closeOnCompletion() throws SQLException {
throw new SQLFeatureNotSupportedException();
}
@Override
public boolean isCloseOnCompletion() throws SQLException {
throw new SQLFeatureNotSupportedException();
}
}