com.google.gerrit.server.plugins.PluginContentScanner Maven / Gradle / Ivy
// Copyright (C) 2014 The Android Open Source Project
//
// 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.google.gerrit.server.plugins;
import java.io.IOException;
import java.io.InputStream;
import java.lang.annotation.Annotation;
import java.nio.file.NoSuchFileException;
import java.util.Collections;
import java.util.Enumeration;
import java.util.Map;
import java.util.Optional;
import java.util.jar.Manifest;
/**
* Scans the plugin returning classes and resources.
*
* Gerrit uses the scanner to automatically discover the classes and resources exported by the
* plugin for auto discovery of exported SSH commands, Servlets and listeners.
*/
public interface PluginContentScanner {
/** Scanner without resources. */
PluginContentScanner EMPTY =
new PluginContentScanner() {
@Override
public Manifest getManifest() throws IOException {
return new Manifest();
}
@Override
public Map, Iterable> scan(
String pluginName, Iterable> annotations)
throws InvalidPluginException {
return Collections.emptyMap();
}
@Override
public Optional getEntry(String resourcePath) {
return Optional.empty();
}
@Override
public InputStream getInputStream(PluginEntry entry) throws IOException {
throw new NoSuchFileException("Empty plugin");
}
@Override
public Enumeration entries() {
return Collections.emptyEnumeration();
}
};
/**
* Plugin class extension meta-data
*
* Class name and annotation value of the class provided by a plugin to extend an existing
* extension point in Gerrit.
*/
class ExtensionMetaData {
public final String className;
public final String annotationValue;
public ExtensionMetaData(String className, String annotationValue) {
this.className = className;
this.annotationValue = annotationValue;
}
}
/**
* Return the plugin meta-data manifest
*
* @return Manifest of the plugin or null if plugin has no meta-data
* @throws IOException if an I/O problem occurred whilst accessing the Manifest
*/
Manifest getManifest() throws IOException;
/**
* Scans the plugin for declared public annotated classes
*
* @param pluginName the plugin name
* @param annotations annotations declared by the plugin classes
* @return map of annotations and associated plugin classes found
* @throws InvalidPluginException if the plugin is not valid or corrupted
*/
Map, Iterable> scan(
String pluginName, Iterable> annotations)
throws InvalidPluginException;
/**
* Return the plugin resource associated to a path
*
* @param resourcePath full path of the resource inside the plugin package
* @return the resource object or Optional.absent() if the resource was not found
* @throws IOException if there was a problem retrieving the resource
*/
Optional getEntry(String resourcePath) throws IOException;
/**
* Return the InputStream of the resource entry
*
* @param entry resource entry inside the plugin package
* @return the resource input stream
* @throws IOException if there was an I/O problem accessing the resource
*/
InputStream getInputStream(PluginEntry entry) throws IOException;
/**
* Return all the resources inside a plugin
*
* @return the enumeration of all resources found
*/
Enumeration entries();
}