public class

UriMatcher

extends Object
java.lang.Object
   ↳ android.content.UriMatcher

Class Overview

Utility class to aid in matching URIs in content providers.

To use this class, build up a tree of UriMatcher objects. Typically, it looks something like this:

    private static final int PEOPLE = 1;
    private static final int PEOPLE_ID = 2;
    private static final int PEOPLE_PHONES = 3;
    private static final int PEOPLE_PHONES_ID = 4;
    private static final int PEOPLE_CONTACTMETHODS = 7;
    private static final int PEOPLE_CONTACTMETHODS_ID = 8;

    private static final int DELETED_PEOPLE = 20;

    private static final int PHONES = 9;
    private static final int PHONES_ID = 10;
    private static final int PHONES_FILTER = 14;

    private static final int CONTACTMETHODS = 18;
    private static final int CONTACTMETHODS_ID = 19;

    private static final int CALLS = 11;
    private static final int CALLS_ID = 12;
    private static final int CALLS_FILTER = 15;

    private static final UriMatcher sURIMatcher = new UriMatcher();

    static
    {
        sURIMatcher.addURI("contacts", "/people", PEOPLE);
        sURIMatcher.addURI("contacts", "/people/#", PEOPLE_ID);
        sURIMatcher.addURI("contacts", "/people/#/phones", PEOPLE_PHONES);
        sURIMatcher.addURI("contacts", "/people/#/phones/#", PEOPLE_PHONES_ID);
        sURIMatcher.addURI("contacts", "/people/#/contact_methods", PEOPLE_CONTACTMETHODS);
        sURIMatcher.addURI("contacts", "/people/#/contact_methods/#", PEOPLE_CONTACTMETHODS_ID);
        sURIMatcher.addURI("contacts", "/deleted_people", DELETED_PEOPLE);
        sURIMatcher.addURI("contacts", "/phones", PHONES);
        sURIMatcher.addURI("contacts", "/phones/filter/*", PHONES_FILTER);
        sURIMatcher.addURI("contacts", "/phones/#", PHONES_ID);
        sURIMatcher.addURI("contacts", "/contact_methods", CONTACTMETHODS);
        sURIMatcher.addURI("contacts", "/contact_methods/#", CONTACTMETHODS_ID);
        sURIMatcher.addURI("call_log", "/calls", CALLS);
        sURIMatcher.addURI("call_log", "/calls/filter/*", CALLS_FILTER);
        sURIMatcher.addURI("call_log", "/calls/#", CALLS_ID);
    }

Then when you need to match match against a URI, call match(Uri), providing the tokenized url you've been given, and the value you want if there isn't a match. You can use the result to build a query, return a type, insert or delete a row, or whatever you need, without duplicating all of the if-else logic you'd otherwise need. Like this:

    public String getType(String[] url)
    {
        int match = sURIMatcher.match(url, NO_MATCH);
        switch (match)
        {
            case PEOPLE:
                return "vnd.android.cursor.dir/person";
            case PEOPLE_ID:
                return "vnd.android.cursor.item/person";
... snip ...
                return "vnd.android.cursor.dir/snail-mail";
            case PEOPLE_ADDRESS_ID:
                return "vnd.android.cursor.item/snail-mail";
            default:
                return null;
        }
    }
instead of
    public String getType(String[] url)
    {
        if (url.length >= 2) {
            if (url[1].equals("people")) {
                if (url.length == 2) {
                    return "vnd.android.cursor.dir/person";
                } else if (url.length == 3) {
                    return "vnd.android.cursor.item/person";
... snip ...
                    return "vnd.android.cursor.dir/snail-mail";
                } else if (url.length == 3) {
                    return "vnd.android.cursor.item/snail-mail";
                }
            }
        }
        return null;
    }

Summary

Constants
int NO_MATCH
Public Constructors
UriMatcher(int code)
Creates the root node of the URI tree.
Public Methods
void addURI(String authority, String path, int code)
Add a URI to match, and the code to return when this URI is matched.
int match(Uri uri)
Try to match against the path in a url.
[Expand]
Inherited Methods
From class java.lang.Object

Constants

public static final int NO_MATCH

Since: API Level 1

Constant Value: -1 (0xffffffff)

Public Constructors

public UriMatcher (int code)

Since: API Level 1

Creates the root node of the URI tree.

Parameters
code the code to match for the root URI

Public Methods

public void addURI (String authority, String path, int code)

Since: API Level 1

Add a URI to match, and the code to return when this URI is matched. URI nodes may be exact match string, the token "*" that matches any text, or the token "#" that matches only numbers.

Parameters
authority the authority to match
path the path to match. * may be used as a wild card for any text, and # may be used as a wild card for numbers.
code the code that is returned when a URI is matched against the given components. Must be positive.

public int match (Uri uri)

Since: API Level 1

Try to match against the path in a url.

Parameters
uri The url whose path we will match against.
Returns
  • The code for the matched node (added using addURI), or -1 if there is no matched node.