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/*
* For work developed by the HSQL Development Group:
*
* Copyright (c) 2001-2019, The HSQL Development Group
* All rights reserved.
*
* Redistribution and use in source and binary forms, with or without
* modification, are permitted provided that the following conditions are met:
*
* Redistributions of source code must retain the above copyright notice, this
* list of conditions and the following disclaimer.
*
* Redistributions in binary form must reproduce the above copyright notice,
* this list of conditions and the following disclaimer in the documentation
* and/or other materials provided with the distribution.
*
* Neither the name of the HSQL Development Group nor the names of its
* contributors may be used to endorse or promote products derived from this
* software without specific prior written permission.
*
* THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS "AS IS"
* AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
* IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
* ARE DISCLAIMED. IN NO EVENT SHALL HSQL DEVELOPMENT GROUP, HSQLDB.ORG,
* OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL,
* EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO,
* PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES;
* LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND
* ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
* (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF THIS
* SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
*
*
*
* For work originally developed by the Hypersonic SQL Group:
*
* Copyright (c) 1995-2000, The Hypersonic SQL Group.
* All rights reserved.
*
* Redistribution and use in source and binary forms, with or without
* modification, are permitted provided that the following conditions are met:
*
* Redistributions of source code must retain the above copyright notice, this
* list of conditions and the following disclaimer.
*
* Redistributions in binary form must reproduce the above copyright notice,
* this list of conditions and the following disclaimer in the documentation
* and/or other materials provided with the distribution.
*
* Neither the name of the Hypersonic SQL Group nor the names of its
* contributors may be used to endorse or promote products derived from this
* software without specific prior written permission.
*
* THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS "AS IS"
* AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
* IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
* ARE DISCLAIMED. IN NO EVENT SHALL THE HYPERSONIC SQL GROUP,
* OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL,
* EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO,
* PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES;
* LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND
* ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
* (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF THIS
* SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
*
* This software consists of voluntary contributions made by many individuals
* on behalf of the Hypersonic SQL Group.
*/
package org.hsqldb.server;
import java.io.DataInputStream;
import java.io.IOException;
import java.io.PrintWriter;
import javax.servlet.ServletConfig;
import javax.servlet.ServletException;
import javax.servlet.http.HttpServlet;
import javax.servlet.http.HttpServletRequest;
import javax.servlet.http.HttpServletResponse;
import org.hsqldb.DatabaseManager;
import org.hsqldb.DatabaseURL;
import org.hsqldb.HsqlException;
import org.hsqldb.Session;
import org.hsqldb.lib.DataOutputStream;
import org.hsqldb.lib.HsqlByteArrayOutputStream;
import org.hsqldb.persist.HsqlProperties;
import org.hsqldb.result.Result;
import org.hsqldb.result.ResultConstants;
import org.hsqldb.rowio.RowInputBinary;
import org.hsqldb.rowio.RowOutputBinary;
// fredt@users 20020130 - patch 475586 by wreissen@users
// fredt@users 20020328 - patch 1.7.0 by fredt - error trapping
// fredt@users 20030630 - patch 1.7.2 - new protocol, persistent sessions
// fredt@users 20041112 - patch by William Crick - use web_inf directory
/**
* Servlet can act as an interface between the client and the database for the
* the client / server mode of HSQL Database Engine. It uses the HTTP protocol
* for communication. This class is not required if the included HSQLDB
* Weberver is used on the server host. But if the host is running a J2EE
* application server or a servlet container such as Tomcat, the Servlet class
* can be hosted on this server / container to serve external requests from
* external hosts.
* The remote applet / application should
* use the normal JDBC interfaces to connect to the URL of this servlet. An
* example URL is:
*
* jdbc:hsqldb:http://myhost.com:8080/servlet/org.hsqldb.server.Servlet
*
* The database path/name is taken from the servlet engine property:
*
* hsqldb.server.database
*
*
* If the database is deployed in the WEB-INF directory of the servlet container,
* the property:
*
* hsqldb.server.use_web-inf_path
*
* should be set "true" in the web.xml file of the servlet container.
* In this case, the database path should begin with a "/".
*
* JDBC connections via the HTTP protocol are persistent
* in the JDBC sense. The JDBC Connection that is established can support
* transactions spanning several Statement calls and real PreparedStatement
* calls are supported.
*
* @author Fred Toussi (fredt@users dot sourceforge.net)
* @version 2.3.4
* @since 1.6.2
*/
public class Servlet extends HttpServlet {
private static final int BUFFER_SIZE = 256;
private String dbType;
private String dbPath;
private String initError;
public void init(ServletConfig config) {
try {
super.init(config);
} catch (ServletException e) {
log(e.toString());
}
String dbStr = getInitParameter("hsqldb.server.database");
if (dbStr == null) {
dbStr = ".";
}
// begin WEB-INF patch */
String useWebInfStr =
getInitParameter("hsqldb.server.use_web-inf_path");
if (!dbStr.equals(".") && "true".equalsIgnoreCase(useWebInfStr)) {
dbStr = getServletContext().getRealPath("/") + "WEB-INF/" + dbStr;
}
// end WEB-INF patch
HsqlProperties dbURL = DatabaseURL.parseURL(dbStr, false, false);
log("Database filename = " + dbStr);
if (dbURL == null) {
initError = "Bad Database name";
} else {
dbPath = dbURL.getProperty("database");
dbType = dbURL.getProperty("connection_type");
try {
DatabaseManager.getDatabase(dbType, dbPath, dbURL);
} catch (HsqlException e) {
initError = e.getMessage();
}
}
if (initError == null) {
log("Initialization completed.");
} else {
log("Database could not be initialised.");
log(initError);
}
}
private static long lModified = 0;
protected long getLastModified(HttpServletRequest req) {
// this is made so that the cache of the http server is not used
// maybe there is some other way
return lModified++;
}
public void doGet(HttpServletRequest request,
HttpServletResponse response)
throws IOException, ServletException {
String query = request.getQueryString();
if ((query == null) || (query.length() == 0)) {
response.setContentType("text/html");
// fredt@users 20020130 - patch 1.7.0 by fredt
// to avoid caching on the browser
response.setHeader("Pragma", "no-cache");
PrintWriter out = response.getWriter();
out.println(
"
HSQL Database Engine Servlet ");
out.println("HSQL Database Engine Servlet
");
out.println("The servlet is running.");
if (initError == null) {
out.println("Connected to the database.
");
out.println("Database name: " + dbType + dbPath + "
");
} else {
out.println("
The database is not available.
");
out.println("The error message is:");
out.println(initError);
}
out.println("");
}
}
public void doPost(HttpServletRequest request,
HttpServletResponse response)
throws IOException, ServletException {
DataInputStream inStream = null;
DataOutputStream dataOut = null;
try {
inStream = new DataInputStream(request.getInputStream());
int databaseID = inStream.readInt();
long sessionID = inStream.readLong();
int mode = inStream.readByte();
RowInputBinary rowIn = new RowInputBinary(BUFFER_SIZE);
Session session = DatabaseManager.getSession(databaseID,
sessionID);
Result resultIn = Result.newResult(session, mode, inStream, rowIn);
resultIn.setDatabaseId(databaseID);
resultIn.setSessionId(sessionID);
Result resultOut;
int type = resultIn.getType();
if (type == ResultConstants.CONNECT) {
try {
session =
DatabaseManager.newSession(dbType, dbPath,
resultIn.getMainString(),
resultIn.getSubString(),
new HsqlProperties(),
resultIn.getZoneString(),
resultIn.getUpdateCount());
resultOut =
Result.newConnectionAcknowledgeResponse(session);
} catch (HsqlException e) {
resultOut = Result.newErrorResult(e);
}
} else if (type == ResultConstants.DISCONNECT
|| type == ResultConstants.RESETSESSION) {
// Upon DISCONNECT 6 bytes are read by the ClientConnectionHTTP": mode (1 byte), a length (int), and an 'additional results (1 byte)
response.setHeader("Cache-Control", "no-cache"); // DB-traffic should not be cached by proxies
response.setContentType("application/octet-stream");
response.setContentLength(6);
// Only acquire output-stream after headers are set
dataOut = new DataOutputStream(response.getOutputStream());
dataOut.writeByte(ResultConstants.DISCONNECT); // Mode
dataOut.writeInt(4); // Length Int of first result is always read! Minvalue is 4: It is the number of bytes of the current result (it includes the length of this Int itself)
dataOut.writeByte(ResultConstants.NONE); // No Additional results
dataOut.close();
return;
} else if (type == ResultConstants.SQLCANCEL) {
int dbId = resultIn.getDatabaseId();
long sessionId = resultIn.getSessionId();
session = DatabaseManager.getSession(dbId, sessionId);
resultOut = session.cancel(resultIn);
} else {
int dbId = resultIn.getDatabaseId();
long sessionId = resultIn.getSessionId();
session = DatabaseManager.getSession(dbId, sessionId);
resultIn.readLobResults(session, inStream, rowIn);
resultOut = session.execute(resultIn);
}
HsqlByteArrayOutputStream memStream =
new HsqlByteArrayOutputStream();
DataOutputStream tempOutput = new DataOutputStream(memStream);
RowOutputBinary rowOut = new RowOutputBinary(BUFFER_SIZE, 1);
resultOut.write(session, tempOutput, rowOut);
response.setHeader("Cache-Control", "no-cache"); // DB-traffic should not be cached by proxies
response.setContentType("application/octet-stream");
response.setContentLength(memStream.size());
// Only acquire output-stream after headers are set
dataOut = new DataOutputStream(response.getOutputStream());
memStream.writeTo(dataOut);
} catch (HsqlException e) {}
finally {
if (dataOut != null) {
dataOut.close();
}
if (inStream != null) {
inStream.close();
}
}
}
}