com.izforge.izpack.installer.requirement.LockFileChecker Maven / Gradle / Ivy
/*
* IzPack - Copyright 2001-2012 Julien Ponge, All Rights Reserved.
*
* http://izpack.org/
* http://izpack.codehaus.org/
*
* Copyright 2012 Tim Anderson
*
* 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 com.izforge.izpack.installer.requirement;
import java.io.File;
import java.util.logging.Level;
import java.util.logging.Logger;
import com.izforge.izpack.api.data.AutomatedInstallData;
import com.izforge.izpack.api.data.Info;
import com.izforge.izpack.api.data.InstallData;
import com.izforge.izpack.api.handler.Prompt;
import com.izforge.izpack.api.handler.Prompt.Option;
import com.izforge.izpack.api.installer.RequirementChecker;
import com.izforge.izpack.util.FileUtil;
/**
* Determines if another installation is in progress, by checking for the existence of a lock file.
*
* @author Tim Anderson
*/
public class LockFileChecker implements RequirementChecker
{
/**
* The installation data.
*/
private final InstallData installData;
/**
* The prompt.
*/
private final Prompt prompt;
/**
* The logger.
*/
private static final Logger logger = Logger.getLogger(LockFileChecker.class.getName());
/**
* Constructs a LockFileChecker.
*
* @param installData the installation data
* @param prompt the prompt
*/
public LockFileChecker(AutomatedInstallData installData, Prompt prompt)
{
this.installData = installData;
this.prompt = prompt;
}
/**
* Determines if installation requirements are met.
*
* @return true if requirements are met, otherwise false
*/
@Override
public boolean check()
{
boolean result = true;
Info installationInfo = installData.getInfo();
if (installationInfo.isSingleInstance() && !Boolean.getBoolean("MULTIINSTANCE"))
{
String appName = installationInfo.getAppName();
File file = FileUtil.getLockFile(appName);
if (file.exists())
{
result = handleLockFile(file);
}
else
{
try
{
// Create the new lock file
if (file.createNewFile())
{
logger.fine("Created lock file:" + file.getPath());
file.deleteOnExit();
}
else
{
logger.warning("Failed to create lock file: " + file.getPath());
logger.warning("*** Multiple instances of installer will be allowed ***");
}
}
catch (Exception e)
{
logger.log(Level.WARNING, "Lock file could not be created: " + e.getMessage(), e);
logger.warning("*** Multiple instances of installer will be allowed ***");
}
result = true;
}
}
return result;
}
/**
* Invoked when the lock file already exists.
*
* @param file the lock file
* @return true if the user wants to proceed with installation, false if they want to cancel
*/
protected boolean handleLockFile(File file)
{
boolean result = true;
logger.fine("Lock File Exists, asking user for permission to proceed.");
StringBuilder msg = new StringBuilder();
String appName = installData.getInfo().getAppName();
msg.append("The " + appName + " installer you are attempting to run seems to have a copy already running.\n\n");
msg.append("This could be from a previous failed installation attempt or you may have accidentally launched\n");
msg.append("the installer twice. The recommended action is to select 'No' and wait for the other copy of\n");
msg.append("the installer to start. If you are sure there is no other copy of the installer running, click\n");
msg.append("the 'Yes' button to allow this installer to run.\n\n");
msg.append("Are you sure you want to continue with this installation?");
Option selected = prompt.confirm(Prompt.Type.WARNING, msg.toString(), Prompt.Options.YES_NO);
if (selected == Option.YES)
{
// Take control of the file so it gets deleted after this installer instance exits.
logger.fine("Setting temp file to delete on continue");
// FIXME Avoid deleting lock for other running instances by using some pool of locks
// (this is just a workaround to clean up)
file.deleteOnExit();
}
else
{
// Leave the file as it is.
logger.fine("Leaving temp file alone and exiting");
result = false;
}
return result;
}
}