contrib/zpages/src/main/java/io/opencensus/contrib/zpages/ZPageHandler.java

/*
 * Copyright 2017, OpenCensus Authors
 *
 * 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 io.opencensus.contrib.zpages;

import java.io.OutputStream;
import java.util.Map;

/**
 * Main interface for all the Z-Pages. All Z-Pages must implement this interface to allow other HTTP
 * server implementation to support these pages.
 *
 * @since 0.6
 */
public abstract class ZPageHandler {

  /**
   * Returns the URL path that should be used to register this page.
   *
   * @return the URL path that should be used to register this page.
   * @since 0.6
   */
  public abstract String getUrlPath();

  /**
   * Emits the HTML generated page to the {@code outputStream}.
   *
   * @param queryMap the query components map.
   * @param outputStream the output {@code OutputStream}.
   * @since 0.6
   */
  public abstract void emitHtml(Map<String, String> queryMap, OutputStream outputStream);

  /** Package protected constructor to disallow users to extend this class. */
  ZPageHandler() {}
}