src/jdk.internal.opt/share/classes/jdk/internal/joptsimple/internal/Rows.java

/*
 * Copyright (c) 2015, Oracle and/or its affiliates. All rights reserved.
 * DO NOT ALTER OR REMOVE COPYRIGHT NOTICES OR THIS FILE HEADER.
 *
 * This code is free software; you can redistribute it and/or modify it
 * under the terms of the GNU General Public License version 2 only, as
 * published by the Free Software Foundation.  Oracle designates this
 * particular file as subject to the "Classpath" exception as provided
 * by Oracle in the LICENSE file that accompanied this code.
 *
 * This code is distributed in the hope that it will be useful, but WITHOUT
 * ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or
 * FITNESS FOR A PARTICULAR PURPOSE.  See the GNU General Public License
 * version 2 for more details (a copy is included in the LICENSE file that
 * accompanied this code).
 *
 * You should have received a copy of the GNU General Public License version
 * 2 along with this work; if not, write to the Free Software Foundation,
 * Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA.
 *
 * Please contact Oracle, 500 Oracle Parkway, Redwood Shores, CA 94065 USA
 * or visit www.oracle.com if you need additional information or have any
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/*
 * This file is available under and governed by the GNU General Public
 * License version 2 only, as published by the Free Software Foundation.
 * However, the following notice accompanied the original version of this
 * file:
 *
 * The MIT License
 *
 * Copyright (c) 2004-2015 Paul R. Holser, Jr.
 *
 * Permission is hereby granted, free of charge, to any person obtaining
 * a copy of this software and associated documentation files (the
 * "Software"), to deal in the Software without restriction, including
 * without limitation the rights to use, copy, modify, merge, publish,
 * distribute, sublicense, and/or sell copies of the Software, and to
 * permit persons to whom the Software is furnished to do so, subject to
 * the following conditions:
 *
 * The above copyright notice and this permission notice shall be
 * included in all copies or substantial portions of the Software.
 *
 * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND,
 * EXPRESS OR IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF
 * MERCHANTABILITY, FITNESS FOR A PARTICULAR PURPOSE AND
 * NONINFRINGEMENT. IN NO EVENT SHALL THE AUTHORS OR COPYRIGHT HOLDERS BE
 * LIABLE FOR ANY CLAIM, DAMAGES OR OTHER LIABILITY, WHETHER IN AN ACTION
 * OF CONTRACT, TORT OR OTHERWISE, ARISING FROM, OUT OF OR IN CONNECTION
 * WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE SOFTWARE.
 */

package jdk.internal.joptsimple.internal;

import java.util.ArrayList;
import java.util.List;

import static java.lang.Math.*;

import static jdk.internal.joptsimple.internal.Strings.*;

/**
 * @author <a href="mailto:pholser@alumni.rice.edu">Paul Holser</a>
 */
public class Rows {
    private final int overallWidth;
    private final int columnSeparatorWidth;
    private final List<Row> rows = new ArrayList<>();

    private int widthOfWidestOption;
    private int widthOfWidestDescription;

    public Rows( int overallWidth, int columnSeparatorWidth ) {
        this.overallWidth = overallWidth;
        this.columnSeparatorWidth = columnSeparatorWidth;
    }

    public void add( String option, String description ) {
        add( new Row( option, description ) );
    }

    private void add( Row row ) {
        rows.add( row );
        widthOfWidestOption = max( widthOfWidestOption, row.option.length() );
        widthOfWidestDescription = max( widthOfWidestDescription, row.description.length() );
    }

    public void reset() {
        rows.clear();
        widthOfWidestOption = 0;
        widthOfWidestDescription = 0;
    }

    public void fitToWidth() {
        Columns columns = new Columns( optionWidth(), descriptionWidth() );

        List<Row> fitted = new ArrayList<>();
        for ( Row each : rows )
            fitted.addAll( columns.fit( each ) );

        reset();

        for ( Row each : fitted )
            add( each );
    }

    public String render() {
        StringBuilder buffer = new StringBuilder();

        for ( Row each : rows ) {
            pad( buffer, each.option, optionWidth() ).append( repeat( ' ', columnSeparatorWidth ) );
            pad( buffer, each.description, descriptionWidth() ).append( LINE_SEPARATOR );
        }

        return buffer.toString();
    }

    private int optionWidth() {
        return min( ( overallWidth - columnSeparatorWidth ) / 2, widthOfWidestOption );
    }

    private int descriptionWidth() {
        return min( overallWidth - optionWidth() - columnSeparatorWidth, widthOfWidestDescription );
    }

    private StringBuilder pad( StringBuilder buffer, String s, int length ) {
        buffer.append( s ).append( repeat( ' ', length - s.length() ) );
        return buffer;
    }
}