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* The contents of this file are subject to the terms of the
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* with the License.
*
* You can obtain a copy of the license at
* docs/licenses/cddl.txt
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* See the License for the specific language governing permissions
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*
* When distributing Covered Code, include this CDDL HEADER in each
* file and include the License file at
* docs/licenses/cddl.txt. If applicable,
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* Copyright 2011-2016 UnboundID Corp.
*/
package com.unboundid.directory.sdk.examples.groovy;
import java.util.Arrays;
import java.util.List;
import com.unboundid.directory.sdk.examples.ExampleHelloServlet;
import com.unboundid.directory.sdk.http.config.HTTPServletExtensionConfig;
import com.unboundid.directory.sdk.http.scripting.ScriptedHTTPServletExtension;
import com.unboundid.directory.sdk.http.types.HTTPServerContext;
import com.unboundid.ldap.sdk.LDAPException;
import com.unboundid.ldap.sdk.ResultCode;
import com.unboundid.util.args.ArgumentException;
import com.unboundid.util.args.ArgumentParser;
import com.unboundid.util.args.StringArgument;
/**
* This class provides a simple example of a scripted HTTP servlet extension
* which will create a simple "Hello, World!" servlet. It has two configuration
* arguments:
* <UL>
* <LI>name -- The name to display in the servlet's hello message. If this is
* not provided, then a default value of "World" will be used.</LI>
* <LI>path -- The path that should be used to invoke the servlet. If this is
* not provided, then a default value of "/hello" will be used.</LI>
* </UL>
*/
public final class ExampleScriptedHTTPServletExtension
extends ScriptedHTTPServletExtension
{
/**
* The name of the argument that will be used to specify the name that should
* be used in the greeting.
*/
private static final String ARG_NAME_NAME = "name";
/**
* The name of the argument that will be used to specify the path that will be
* used to access the servlet.
*/
private static final String ARG_NAME_PATH = "path";
// The servlet that has been created.
private volatile ExampleHelloServlet servlet;
// The path that will be used for the servlet.
private volatile String path;
/**
* Creates a new instance of this HTTP servlet extension. All HTTP servlet
* extension implementations must include a default constructor, but any
* initialization should generally be done in the {@code createServlet}
* method.
*/
public ExampleScriptedHTTPServletExtension()
{
servlet = null;
path = null;
}
/**
* Updates the provided argument parser to define any configuration arguments
* which may be used by this HTTP servlet extension. The argument parser
* may also be updated to define relationships between arguments (e.g., to
* specify required, exclusive, or dependent argument sets).
*
* @param parser The argument parser to be updated with the configuration
* arguments which may be used by this HTTP servlet
* extension.
*
* @throws ArgumentException If a problem is encountered while updating the
* provided argument parser.
*/
@Override()
public void defineConfigArguments(final ArgumentParser parser)
throws ArgumentException
{
// Add an argument that allows you to specify the name to use in the
// greeting.
Character shortIdentifier = null;
String longIdentifier = ARG_NAME_NAME;
boolean required = false;
int maxOccurrences = 1;
String placeholder = "{name}";
String description = "The name to use in the greeting.";
String defaultValue = "World";
parser.addArgument(new StringArgument(shortIdentifier, longIdentifier,
required, maxOccurrences, placeholder, description, defaultValue));
// Add an argument that allows you to specify the request path.
shortIdentifier = null;
longIdentifier = ARG_NAME_PATH;
required = false;
maxOccurrences = 1;
placeholder = "{path}";
description = "The path to use to access the servlet. Note that " +
"changes to this argument will only take effect if the associated " +
"HTTP connection handler (or the entire server) is stopped and " +
"re-started.";
defaultValue = "/hello";
parser.addArgument(new StringArgument(shortIdentifier, longIdentifier,
required, maxOccurrences, placeholder, description, defaultValue));
}
/**
* Creates an HTTP servlet extension using the provided information.
*
* @param serverContext A handle to the server context for the server in
* which this extension is running.
* @param config The general configuration for this HTTP servlet
* extension.
* @param parser The argument parser which has been initialized from
* the configuration for this HTTP servlet extension.
*
* @return The HTTP servlet that has been created.
*
* @throws LDAPException If a problem is encountered while attempting to
* create the HTTP servlet.
*/
@Override()
public ExampleHelloServlet createServlet(
final HTTPServerContext serverContext,
final HTTPServletExtensionConfig config,
final ArgumentParser parser)
throws LDAPException
{
// Get the new greeting name.
final StringArgument nameArg =
(StringArgument) parser.getNamedArgument(ARG_NAME_NAME);
// Get the servlet path.
final StringArgument pathArg =
(StringArgument) parser.getNamedArgument(ARG_NAME_PATH);
path = pathArg.getValue();
servlet = new ExampleHelloServlet(nameArg.getValue());
return servlet;
}
/**
* Retrieves a list of the request paths for which the associated servlet
* should be invoked. This method will be called after the
* {@link #createServlet} method has been used to create the servlet instance.
*
* @return A list of the request paths for which the associated servlet
* should be invoked.
*/
@Override()
public List<String> getServletPaths()
{
return Arrays.asList(path);
}
/**
* Indicates whether the configuration contained in the provided argument
* parser represents a valid configuration for this extension.
*
* @param config The general configuration for this HTTP
* servlet extension.
* @param parser The argument parser which has been initialized
* with the proposed configuration.
* @param unacceptableReasons A list that can be updated with reasons that
* the proposed configuration is not acceptable.
*
* @return {@code true} if the proposed configuration is acceptable, or
* {@code false} if not.
*/
@Override()
public boolean isConfigurationAcceptable(
final HTTPServletExtensionConfig config,
final ArgumentParser parser,
final List<String> unacceptableReasons)
{
// No special validation is required.
return true;
}
/**
* Attempts to apply the configuration contained in the provided argument
* parser.
*
* @param config The general configuration for this HTTP
* servlet extension.
* @param parser The argument parser which has been
* initialized with the new configuration.
* @param adminActionsRequired A list that can be updated with information
* about any administrative actions that may be
* required before one or more of the
* configuration changes will be applied.
* @param messages A list that can be updated with information
* about the result of applying the new
* configuration.
*
* @return A result code that provides information about the result of
* attempting to apply the configuration change.
*/
@Override()
public ResultCode applyConfiguration(final HTTPServletExtensionConfig config,
final ArgumentParser parser,
final List<String> adminActionsRequired,
final List<String> messages)
{
// We only need to validate changes made after the servlet has been created.
// If the servlet hasn't yet been created, then we don't need to do
// anything.
if (servlet == null)
{
return ResultCode.SUCCESS;
}
// Get the new greeting name.
final StringArgument nameArg =
(StringArgument) parser.getNamedArgument(ARG_NAME_NAME);
servlet.setName(nameArg.getValue());
// The path will not change dynamically. If a different path was given,
// then report that as a required administrative action.
final StringArgument pathArg =
(StringArgument) parser.getNamedArgument(ARG_NAME_PATH);
if (! path.equals(pathArg.getValue()))
{
adminActionsRequired.add("Changes to the servlet path will not take " +
"effect until the HTTP connection handler (or entire server) is " +
"restarted.");
}
return ResultCode.SUCCESS;
}
}
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