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/*
 * Copyright (C) 2007 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 android.content;

import android.net.Uri;


Utility methods useful for working with Uri objects that use the "content" (content://) scheme. 

  Content URIs have the syntax




  content://authority/path/id




  

      content:
  

  
 The scheme portion of the URI. This is always set to ContentResolver.SCHEME_CONTENT (value content://).
  

  

      authority
  

  

      A string that identifies the entire content provider. All the content URIs for the provider
      start with this string. To guarantee a unique authority, providers should consider
      using an authority that is the same as the provider class' package identifier.
  

  

      path
  

  

      Zero or more segments, separated by a forward slash (/), that identify
      some subset of the provider's data. Most providers use the path part to identify
      individual tables. Individual segments in the path are often called
      "directories" although they do not refer to file directories. The right-most
      segment in a path is often called a "twig"
  

  

      id
  

  

      A unique numeric identifier for a single row in the subset of data identified by the
      preceding path part. Most providers recognize content URIs that contain an id part
      and give them special handling. A table that contains a column named _ID
      often expects the id part to be a particular value for that column.
  




/**
* Utility methods useful for working with {@link android.net.Uri} objects
* that use the "content" (content://) scheme.
*
*<p>
*   Content URIs have the syntax
*</p>
*<p>
*   <code>content://<em>authority</em>/<em>path</em>/<em>id</em></code>
*</p>
*<dl>
*   <dt>
*       <code>content:</code>
*   </dt>
*   <dd>
*       The scheme portion of the URI. This is always set to {@link
*       android.content.ContentResolver#SCHEME_CONTENT ContentResolver.SCHEME_CONTENT} (value
*       <code>content://</code>).
*   </dd>
*   <dt>
*       <em>authority</em>
*   </dt>
*   <dd>
*       A string that identifies the entire content provider. All the content URIs for the provider
*       start with this string. To guarantee a unique authority, providers should consider
*       using an authority that is the same as the provider class' package identifier.
*   </dd>
*   <dt>
*       <em>path</em>
*   </dt>
*   <dd>
*       Zero or more segments, separated by a forward slash (<code>/</code>), that identify
*       some subset of the provider's data. Most providers use the path part to identify
*       individual tables. Individual segments in the path are often called
*       &quot;directories&quot; although they do not refer to file directories. The right-most
*       segment in a path is often called a &quot;twig&quot;
*   </dd>
*   <dt>
*       <em>id</em>
*   </dt>
*   <dd>
*       A unique numeric identifier for a single row in the subset of data identified by the
*       preceding path part. Most providers recognize content URIs that contain an id part
*       and give them special handling. A table that contains a column named <code>_ID</code>
*       often expects the id part to be a particular value for that column.
*   </dd>
*</dl>
*
*/
public class ContentUris {

    
Converts the last path segment to a long.

This supports a common convention for content URIs where an ID is
stored in the last segment.

Throws:
  • UnsupportedOperationException – if this isn't a hierarchical URI
  • NumberFormatException – if the last segment isn't a number
Returns:the long conversion of the last segment or -1 if the path is
 empty
/**
     * Converts the last path segment to a long.
     *
     * <p>This supports a common convention for content URIs where an ID is
     * stored in the last segment.
     *
     * @throws UnsupportedOperationException if this isn't a hierarchical URI
     * @throws NumberFormatException if the last segment isn't a number
     *
     * @return the long conversion of the last segment or -1 if the path is
     *  empty
     */
    public static long parseId(Uri contentUri) {
        String last = contentUri.getLastPathSegment();
        return last == null ? -1 : Long.parseLong(last);
    }

    
Appends the given ID to the end of the path.

Params:
  • builder – to append the ID to
  • id – to append
Returns:the given builder
/**
     * Appends the given ID to the end of the path.
     *
     * @param builder to append the ID to
     * @param id to append
     *
     * @return the given builder
     */
    public static Uri.Builder appendId(Uri.Builder builder, long id) {
        return builder.appendEncodedPath(String.valueOf(id));
    }

    
Appends the given ID to the end of the path.

Params:
  • contentUri – to start with
  • id – to append
Returns:a new URI with the given ID appended to the end of the path
/**
     * Appends the given ID to the end of the path.
     *
     * @param contentUri to start with
     * @param id to append
     *
     * @return a new URI with the given ID appended to the end of the path
     */
    public static Uri withAppendedId(Uri contentUri, long id) {
        return appendId(contentUri.buildUpon(), id).build();
    }
}