com.izforge.izpack.panels.licence.LicenceLoader Maven / Gradle / Ivy
/*
* IzPack - Copyright 2001-2017 The IzPack project team.
* All Rights Reserved.
*
* http://izpack.org/
*
* 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.panels.licence;
import com.izforge.izpack.api.data.Panel;
import com.izforge.izpack.api.exception.ResourceException;
import com.izforge.izpack.api.exception.ResourceNotFoundException;
import com.izforge.izpack.api.resource.Resources;
import com.izforge.izpack.installer.util.PanelHelper;
import org.apache.commons.io.Charsets;
import org.apache.commons.io.IOUtils;
import java.io.IOException;
import java.io.InputStream;
import java.net.URL;
/**
* Provides shared licence loading logic between console and GUI panels.
*
* A licence resource file is identified by its resource name plus a suffix.
* The resource name is built from the simple class name of the IzPanel class
* related to the given {@code panelClass}. The suffix is built from the
* identifier of the given {@code panel}, if available. Otherwise a default
* suffix of {@code "licence"} is used.
*
*
* @author Michael Aichler
*/
class LicenceLoader {
private final static String DEFAULT_SUFFIX = ".licence";
private final Panel panel;
private final Class panelClass;
private final Resources resources;
/**
* Creates a new licence loader.
*
* @param panelClass The class of the concrete licence panel implementation.
* @param panel The panel metadata (needed for the panel identifier).
* @param resources The resource locator.
*/
LicenceLoader(Class panelClass, Panel panel, Resources resources) {
this.panel = panel;
this.panelClass = panelClass;
this.resources = resources;
}
/**
* Loads the licence as a URL.
*
* @return The URL to the resource.
* @throws ResourceException If the related IzPanel or the licence resource
* cannot be found. The generated error message is ready to be logged.
*/
URL asURL() throws ResourceException
{
Class targetClass = findTargetClass(panelClass);
String resourceNamePrefix = targetClass.getSimpleName();
String defaultResourceName = resourceNamePrefix + DEFAULT_SUFFIX;
String specificResourceName = buildSpecificResourceName(resourceNamePrefix, panel);
try
{
if (null != specificResourceName)
{
return resources.getURL(specificResourceName);
}
}
catch (ResourceNotFoundException ignored)
{
}
try
{
return resources.getURL(defaultResourceName);
}
catch (ResourceNotFoundException ignored)
{
}
String message = buildFinalErrorMessage(resourceNamePrefix, defaultResourceName,
specificResourceName);
throw new ResourceNotFoundException(message);
}
/**
* Loads the licence into a string using UTF-8 as encoding.
*
* @return A string representation of the licence.
* @throws ResourceException If the licence could not be found or if file
* content could not be converted to UTF-8.
*/
String asString() throws ResourceException
{
return asString("UTF-8");
}
/**
* Loads the licence into a string with the specified {@code encoding}.
*
* @param encoding The target character encoding.
* @return A string representation of the licence in the specified encoding.
* @throws ResourceException If the licence could not be found or if file
* content could not be converted to the specified {@code encoding}.
*/
String asString(final String encoding) throws ResourceException
{
URL url = asURL();
InputStream in = null;
try
{
in = url.openStream();
return IOUtils.toString(in, Charsets.toCharset(encoding));
}
catch (IOException e)
{
throw new ResourceNotFoundException("Cannot convert license document from resource " +
url.getFile() + " to text: " + e.getMessage());
}
finally
{
IOUtils.closeQuietly(in);
}
}
/**
* Finds the IzPanel target class for the given {@code panelClass}.
*
* @param panelClass The panel class.
* @return The related IzPanel class.
* @throws ResourceException If a related IzPanel class could not be found.
*
* @see PanelHelper#getIzPanel(String)
*/
static Class findTargetClass(Class panelClass) throws ResourceException
{
Class targetClass = PanelHelper.getIzPanel(panelClass.getName());
if (null == targetClass)
{
throw new ResourceNotFoundException("No IzPanel implementation found for " +
panelClass.getSimpleName());
}
return targetClass;
}
/**
* Builds the resource name for a specific panel id.
*
* @param resourceNamePrefix The resource name prefix.
* @param panel The panel providing a specific id.
* @return The specific resource name or {@code null}, if the panel does not
* have an identifier.
*/
static String buildSpecificResourceName(String resourceNamePrefix, Panel panel)
{
if (null != panel)
{
if (panel.hasPanelId())
{
return resourceNamePrefix + '.' + panel.getPanelId();
}
}
return null;
}
/**
* Builds an informative error message.
*
* @param panelType The panel type.
* @param resourceNames The list of evaluated resource names
* @return The built error message.
*/
static String buildFinalErrorMessage(String panelType, String... resourceNames)
{
StringBuilder sb = new StringBuilder();
sb.append("Cannot open any of the possible license document resources (");
boolean isFirst = true;
for (String resourceName : resourceNames)
{
if (null != resourceName)
{
if (!isFirst)
{
sb.append(", ");
}
sb.append(resourceName);
if (isFirst)
{
isFirst = false;
}
}
}
sb.append(") for panel type '");
sb.append(panelType);
sb.append("'");
return sb.toString();
}
}