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ActiveAndroid fork with reactive extensions.

There is a newer version: 3.1.5

package com.activeandroid.sqlbrite;

import android.database.Cursor;

import rx.Observable;
import rx.Subscriber;
import rx.exceptions.Exceptions;
import rx.exceptions.OnErrorThrowable;
import rx.functions.Func1;

final class QueryToOneOperator implements Observable.Operator {
  private final Func1 mapper;
  private boolean emitDefault;
  private T defaultValue;

  QueryToOneOperator(Func1 mapper, boolean emitDefault, T defaultValue) {
    this.mapper = mapper;
    this.emitDefault = emitDefault;
    this.defaultValue = defaultValue;
  }

  @Override public Subscriber call(final Subscriber subscriber) {
    return new Subscriber(subscriber) {
      @Override public void onNext(SqlBrite.Query query) {
        try {
          T item = null;
          Cursor cursor = query.run();
          try {
            if (cursor.moveToNext()) {
              item = mapper.call(cursor);
              if (item == null) {
                throw new NullPointerException("Mapper returned null for row 1");
              }
              if (cursor.moveToNext()) {
                throw new IllegalStateException("Cursor returned more than 1 row");
              }
            }
          } finally {
            cursor.close();
          }
          if (!subscriber.isUnsubscribed()) {
            if (item != null) {
              subscriber.onNext(item);
            } else if (emitDefault) {
              subscriber.onNext(defaultValue);
            }
          }
        } catch (Throwable e) {
          Exceptions.throwIfFatal(e);
          onError(OnErrorThrowable.addValueAsLastCause(e, query.toString()));
        }
      }

      @Override public void onCompleted() {
        subscriber.onCompleted();
      }

      @Override public void onError(Throwable e) {
        subscriber.onError(e);
      }
    };
  }
}