/*
* Copyright 2000-2016 JetBrains s.r.o.
*
* 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.intellij.openapi.actionSystem;
import org.jetbrains.annotations.NonNls;
import org.jetbrains.annotations.NotNull;
import org.jetbrains.annotations.Nullable;
/**
* Allows an action to retrieve information about the context in which it was invoked.
*
* @see AnActionEvent#getDataContext()
* @see com.intellij.openapi.actionSystem.PlatformDataKeys
* @see DataKey
* @see com.intellij.ide.DataManager
* @see DataProvider
*/
public interface DataContext {
/**
* Returns the object corresponding to the specified data identifier. Some of the supported
* data identifiers are defined in the {@link com.intellij.openapi.actionSystem.PlatformDataKeys} class.
*
* @param dataId the data identifier for which the value is requested.
* @return the value, or null if no value is available in the current context for this identifier.
*/
@Nullable
Object getData(@NonNls String dataId);
DataContext EMPTY_CONTEXT = new DataContext() {
@Nullable
@Override
public Object getData(@NonNls String dataId) {
return null;
}
};
/**
* Returns the value corresponding to the specified data key. Some of the supported
* data identifiers are defined in the {@link com.intellij.openapi.actionSystem.PlatformDataKeys} class.
*
* @param key the data key for which the value is requested.
* @return the value, or null if no value is available in the current context for this identifier.
*/
@Nullable
default <T> T getData(@NotNull DataKey<T> key) {
return (T)getData(key.getName());
}
}