/*
 * Licensed to the Apache Software Foundation (ASF) under one
 * or more contributor license agreements.  See the NOTICE file
 * distributed with this work for additional information
 * regarding copyright ownership.  The ASF licenses this file
 * to you 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
 *
 *   https://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.
 *
 *   SPDX-License-Identifier: Apache-2.0
 */

package org.apache.jena.sparql.engine.iterator;

import java.util.NoSuchElementException;

import org.apache.jena.atlas.io.IndentedWriter;
import org.apache.jena.atlas.lib.Lib;
import org.apache.jena.sparql.engine.ExecutionContext;
import org.apache.jena.sparql.engine.binding.Binding;
import org.apache.jena.sparql.serializer.SerializationContext;

/** A query iterator that yields the same thing N times. */

public class QueryIterYieldN extends QueryIter {
    protected int limitYielded;
    protected int countYielded = 0;
    protected Binding binding;

    public QueryIterYieldN(int num, Binding b) {
        this(num, b, null);
    }

    public QueryIterYieldN(int num, Binding b, ExecutionContext context) {
        super(context);
        binding = b;
        limitYielded = num;
    }

    public Binding getBinding() {
        return binding;
    }

    @Override
    protected boolean hasNextBinding() {
        return countYielded < limitYielded;
    }

    @Override
    protected Binding moveToNextBinding() {
        if ( !hasNextBinding() )
            // Try to get the class name as specific as possible for subclasses
            throw new NoSuchElementException(Lib.className(this));
        countYielded++;
        return binding;
    }

    @Override
    protected void closeIterator() {
        // binding = null ;
    }

    @Override
    public void output(IndentedWriter out, SerializationContext sCxt) {
        out.print("QueryIterYieldN: " + limitYielded + " of " + binding);
    }

}
