datatype.java

用java写的ftp服务器程序

/*
 * Copyright 2004 The Apache Software Foundation
 *
 * 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 org.apache.ftpserver.ftplet;

/**
 * Type safe enum for describing the data type
 *
 * @author <a href="mailto:[e-mail]">Niklas Gustavsson</a>
 */
public class DataType {

    /**
     * Binary data type
     */
    public static final DataType BINARY = new DataType("I");
    
    /**
     * ASCII data type
     */
    public static final DataType ASCII = new DataType("A");
    
    /**
     * Parses the argument value from the TYPE command into
     * the type safe class
     * 
     * @param argument The argument value from the TYPE command.
     *     Not case sensitive
     * @return The appropriate data type
     * @throws IllegalArgumentException If the data type is unknown
     */
    public static DataType parseArgument(char argument) {
        switch(argument) {
        case 'A':
        case 'a':
            return ASCII;
        case 'I':
        case 'i':
            return BINARY;
        default:
            throw new IllegalArgumentException("Unknown data type: " + argument);
        }
    }
    
    private String type;
    
    /**
     * Private constructor.
     */
    private DataType(String type) {
        this.type = type;
    }

    /**
     * Return the data type string.
     */
    public String toString() {
        return type;
    }    
}