src.android.content.ContentUris Maven / Gradle / Ivy
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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.annotation.NonNull;
import android.net.Uri;
import java.util.List;
/**
* Utility methods useful for working with {@link android.net.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 {@link
* android.content.ContentResolver#SCHEME_CONTENT 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.
*
*
*
*/
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
* @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(@NonNull Uri contentUri) {
String last = contentUri.getLastPathSegment();
return last == null ? -1 : Long.parseLong(last);
}
/**
* 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 @NonNull Uri.Builder appendId(@NonNull Uri.Builder builder, long id) {
return builder.appendEncodedPath(String.valueOf(id));
}
/**
* 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 @NonNull Uri withAppendedId(@NonNull Uri contentUri, long id) {
return appendId(contentUri.buildUpon(), id).build();
}
/**
* Removes any ID from the end of the path.
*
* @param contentUri that ends with an ID
* @return a new URI with the ID removed from the end of the path
* @throws IllegalArgumentException when the given URI has no ID to remove
* from the end of the path
*/
public static @NonNull Uri removeId(@NonNull Uri contentUri) {
// Verify that we have a valid ID to actually remove
final String last = contentUri.getLastPathSegment();
if (last == null) {
throw new IllegalArgumentException("No path segments to remove");
} else {
Long.parseLong(last);
}
final List segments = contentUri.getPathSegments();
final Uri.Builder builder = contentUri.buildUpon();
builder.path(null);
for (int i = 0; i < segments.size() - 1; i++) {
builder.appendPath(segments.get(i));
}
return builder.build();
}
}