com.nesscomputing.mojo.numbers.NumberField.java Source code

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Here is the source code for com.nesscomputing.mojo.numbers.NumberField.java

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/**
 * Copyright (C) 2011 Ness Computing, Inc.
 *
 * Licensed 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
 *
 * http://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.
 */
package com.nesscomputing.mojo.numbers;

import static java.lang.String.format;

import java.io.IOException;
import java.util.List;
import java.util.regex.Matcher;
import java.util.regex.Pattern;

import org.apache.commons.lang3.ArrayUtils;
import org.apache.commons.lang3.StringUtils;

import com.nesscomputing.mojo.numbers.beans.NumberDefinition;

import com.google.common.base.Preconditions;
import com.google.common.collect.Lists;

public class NumberField implements PropertyElement {
    private static final Pattern MATCH_GROUPS = Pattern.compile("\\d+|[^\\d]+");

    private final NumberDefinition numberDefinition;
    private final ValueProvider valueProvider;

    private final List<String> elements = Lists.newArrayList();
    private final List<Integer> numberElements = Lists.newArrayList();

    public static List<NumberField> createNumbers(final PropertyCache propertyCache,
            final NumberDefinition[] numberDefinitions) throws IOException {
        final List<NumberField> result = Lists.newArrayList();

        if (!ArrayUtils.isEmpty(numberDefinitions)) {
            for (NumberDefinition numberDefinition : numberDefinitions) {
                numberDefinition.check();
                final ValueProvider numberValue = propertyCache.getPropertyValue(numberDefinition);
                final NumberField numberField = new NumberField(numberDefinition, numberValue);
                result.add(numberField);
            }
        }
        return result;
    }

    public NumberField(final NumberDefinition numberDefinition, final ValueProvider valueProvider) {
        this.numberDefinition = numberDefinition;
        this.valueProvider = valueProvider;
    }

    @Override
    public String getPropertyName() {
        // This is not the property name (because many definitions can map onto one prop)
        // but the actual id.
        return numberDefinition.getId();
    }

    @Override
    public String getPropertyValue() {
        parse();
        final String value = StringUtils.join(elements, null);
        final String format = numberDefinition.getFormat();
        return format == null ? value : format(format, value);
    }

    @Override
    public boolean isExport() {
        return numberDefinition.isExport();
    }

    private void parse() {
        final String value = valueProvider.getValue();

        final Matcher m = MATCH_GROUPS.matcher(value);
        elements.clear();
        numberElements.clear();

        while (m.find()) {
            final String matchValue = m.group();
            elements.add(matchValue);
            if (isNumber(matchValue)) {
                numberElements.add(elements.size() - 1);
            }
        }

        Preconditions.checkState(numberElements.size() > numberDefinition.getFieldNumber(),
                "Only %d fields in %s, field %d requested.", numberElements.size(), value,
                numberDefinition.getFieldNumber());
    }

    private boolean isNumber(final CharSequence c) {
        for (int i = 0; i < c.length(); i++) {
            if (!Character.isDigit(c.charAt(i))) {
                return false;
            }
        }
        return true;
    }

    public void increment() {
        final Long value = getNumberValue();
        if (value != null) {
            setNumberValue(value + numberDefinition.getIncrement());
        }
    }

    public void setNumberValue(final Long value) {
        parse();
        if (!numberElements.isEmpty()) {
            elements.set(numberElements.get(numberDefinition.getFieldNumber()), value.toString());
            valueProvider.setValue(StringUtils.join(elements, null));
        }
    }

    public Long getNumberValue() {
        parse();
        return numberElements.isEmpty() ? null
                : new Long(elements.get(numberElements.get(numberDefinition.getFieldNumber())));
    }

    @Override
    public String toString() {
        return getPropertyValue();
    }
}