internal.sdmxdl.EmptyCursor Maven / Gradle / Ivy

Go to download
Show more of this group Show more artifacts with this name
Show all versions of sdmx-dl-api Show documentation
Easily download official statistics - API
There is a newer version: 3.0.0-beta.13
/*
 * Copyright 2017 National Bank of Belgium
 *
 * Licensed under the EUPL, Version 1.1 or - as soon they will be approved
 * by the European Commission - subsequent versions of the EUPL (the "Licence");
 * You may not use this work except in compliance with the Licence.
 * You may obtain a copy of the Licence at:
 *
 * http://ec.europa.eu/idabc/eupl
 *
 * Unless required by applicable law or agreed to in writing, software
 * distributed under the Licence is distributed on an "AS IS" basis,
 * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
 * See the Licence for the specific language governing permissions and
 * limitations under the Licence.
 */
package internal.sdmxdl;

import org.checkerframework.checker.nullness.qual.NonNull;
import sdmxdl.*;

import java.io.IOException;
import java.time.LocalDateTime;
import java.util.Map;
import java.util.Objects;
import java.util.stream.Stream;

/**
 * @author Philippe Charles
 */
public final class EmptyCursor implements DataCursor {

    private boolean closed = false;

    @Override
    public boolean nextSeries() throws IOException {
        checkState();
        return false;
    }

    @Override
    public boolean nextObs() throws IOException {
        checkState();
        throw new IllegalStateException();
    }

    @Override
    public Key getSeriesKey() throws IOException {
        checkState();
        throw new IllegalStateException();
    }

    @Override
    public Frequency getSeriesFrequency() throws IOException {
        checkState();
        throw new IllegalStateException();
    }

    @Override
    public String getSeriesAttribute(String key) throws IOException {
        checkState();
        throw new IllegalStateException();
    }

    @Override
    public Map getSeriesAttributes() throws IOException {
        checkState();
        throw new IllegalStateException();
    }

    @Override
    public LocalDateTime getObsPeriod() throws IOException {
        checkState();
        throw new IllegalStateException();
    }

    @Override
    public Double getObsValue() throws IOException {
        checkState();
        throw new IllegalStateException();
    }

    @Override
    public Map getObsAttributes() throws IOException {
        checkState();
        throw new IllegalStateException();
    }

    @Override
    public void close() {
        closed = true;
    }

    @Override
    public Stream toStream() {
        return Stream.empty();
    }

    @Override
    public @NonNull DataCursor filter(@NonNull Key ref, @NonNull DataFilter filter) {
        Objects.requireNonNull(ref);
        Objects.requireNonNull(filter);
        return this;
    }

    private void checkState() throws IOException {
        if (closed) {
            throw new IOException("Cursor closed");
        }
    }
}