/*
    * Copyright 2013 the original author or authors.
    *
    * 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.orangesignal.csv.bean;
  
  import java.lang.reflect.InvocationTargetException;
  import java.text.Format;
  
  /**
   * {@link Format} に関するユーティリティを提供します。
   * 
   * @author Koji Sugisawa
   * @since 1.4.0
   */
  abstract class FormatUtils {
  
  	/**
  	 * インスタンス化できない事を強制します。
  	 */
  	protected FormatUtils() {
  	}
  
  	public static Format mergeFormatPattern(final Format format, final Format... formats) {
  		final StringBuilder buf = new StringBuilder();
  		buf.append(getFormatPattern(format));
  		for (final Format fmt : formats) {
  			buf.append(getFormatPattern(fmt));
  		}
  
  		final Format result = (Format) format.clone();
  		try {
  			result.getClass().getMethod("applyPattern", String.class).invoke(result, buf.toString());
  		} catch (final NoSuchMethodException e) {
  			throw new IllegalStateException(e.getMessage(), e);
  		} catch (final IllegalAccessException e) {
  			throw new IllegalStateException(e.getMessage(), e);
  		} catch (final InvocationTargetException e) {
  			throw new IllegalStateException(e.getMessage(), e);
  		}
  		return result;
  	}
  
  	private static String getFormatPattern(final Format format) {
  		try {
  			return (String) format.getClass().getMethod("toPattern").invoke(format);
  		} catch (final NoSuchMethodException e) {
  			throw new IllegalStateException(e.getMessage(), e);
  		} catch (final IllegalAccessException e) {
  			throw new IllegalStateException(e.getMessage(), e);
  		} catch (final InvocationTargetException e) {
  			throw new IllegalStateException(e.getMessage(), e);
  		}
  	}
  
  }