RangeScanExample.java

import java.util.List;

import org.junit.Test;
import org.slim3.datastore.Datastore;
import org.slim3.tester.AppEngineTestCase;

import com.google.appengine.api.datastore.Entity;
import com.google.appengine.api.datastore.Key;

import static com.google.appengine.api.datastore.Query.FilterOperator.*;
import static org.hamcrest.Matchers.*;

import static org.junit.Assert.*;

public class RangeScanExample extends AppEngineTestCase {

  @Test
  public void llapi01() {
    Key start = Datastore.createKey("MyKind", "score00010:");
    Key end = Datastore.createKey("MyKind", "score00030:" + "\ufffd");
    List<Key> keyList =
        Datastore.query("MyKind")
          .filter(Entity.KEY_RESERVED_PROPERTY, GREATER_THAN_OR_EQUAL, start)
          .filter(Entity.KEY_RESERVED_PROPERTY, LESS_THAN, end).sort("__key__")
          .asKeyList();
    assertThat(keyList.size(), is(3));
    assertThat(keyList.get(0).getName(), endsWith(":userA"));
    assertThat(keyList.get(1).getName(), endsWith(":userB"));
    assertThat(keyList.get(2).getName(), endsWith(":userC"));
  }

  @Test
  public void llapi02() {
    Key start = Datastore.createKey("MyKind", "score00011:");
    Key end = Datastore.createKey("MyKind", "score00030:" + "\ufffd");
    List<Key> keyList =
        Datastore.query("MyKind")
          .filter(Entity.KEY_RESERVED_PROPERTY, GREATER_THAN_OR_EQUAL, start)
          .filter(Entity.KEY_RESERVED_PROPERTY, LESS_THAN, end).sort("__key__")
          .asKeyList();
    assertThat(keyList.size(), is(2));
    assertThat(keyList.get(0).getName(), endsWith(":userB"));
    assertThat(keyList.get(1).getName(), endsWith(":userC"));
  }

  @Test
  public void llapi03() {
    Key start = Datastore.createKey("MyKind", "score00030:");
    Key end = Datastore.createKey("MyKind", "score00100:" + "\ufffd");
    List<Key> keyList =
        Datastore.query("MyKind")
          .filter(Entity.KEY_RESERVED_PROPERTY, GREATER_THAN_OR_EQUAL, start)
          .filter(Entity.KEY_RESERVED_PROPERTY, LESS_THAN, end).sort("__key__")
          .asKeyList();
    assertThat(keyList.size(), is(2));
    assertThat(keyList.get(0).getName(), endsWith(":userC"));
    assertThat(keyList.get(1).getName(), endsWith(":userE"));
  }

  @Override
  public void setUp() throws Exception {
    super.setUp();
    Key[] keys = {
      Datastore.createKey("MyKind", "score00010:userA"),
      Datastore.createKey("MyKind", "score00011:userB"),
      Datastore.createKey("MyKind", "score00030:userC"),
      Datastore.createKey("MyKind", "score00005:userD"),
      Datastore.createKey("MyKind", "score00100:userE"),
      Datastore.createKey("MyKind", "score00009:userF")
    };
    for (Key key : keys) {
      Entity entity = new Entity(key);
      Datastore.put(entity);
    }
  }
}