generictypevalidator.java

java验证框架 java验证框架

/*
 * 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
 *
 *      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.commons.validator;

import java.io.Serializable;
import java.util.Date;
import java.util.Locale;
import java.text.DateFormat;
import java.text.SimpleDateFormat;
import java.text.NumberFormat;
import java.text.ParseException;
import java.text.ParsePosition;
import org.apache.commons.logging.Log;
import org.apache.commons.logging.LogFactory;

/**
 *  This class contains basic methods for performing validations that return the
 *  correctly typed class based on the validation performed.
 *
 * @version $Revision: 478334 $ $Date: 2006-11-22 21:31:54 +0000 (Wed, 22 Nov 2006) $
 */
public class GenericTypeValidator implements Serializable {

    /**
     *  Checks if the value can safely be converted to a byte primitive.
     *
     *@param  value  The value validation is being performed on.
     *@return the converted Byte value.
     */
    public static Byte formatByte(String value) {
        if (value == null) {
            return null;
        }

        try {
            return new Byte(value);
        } catch (NumberFormatException e) {
            return null;
        }

    }

    /**
     *  Checks if the value can safely be converted to a byte primitive.
     *
     *@param  value   The value validation is being performed on.
     *@param  locale  The locale to use to parse the number (system default if
     *      null)
     *@return the converted Byte value.
     */
    public static Byte formatByte(String value, Locale locale) {
        Byte result = null;

        if (value != null) {
            NumberFormat formatter = null;
            if (locale != null) {
                formatter = NumberFormat.getNumberInstance(locale);
            } else {
                formatter = NumberFormat.getNumberInstance(Locale.getDefault());
            }
            formatter.setParseIntegerOnly(true);
            ParsePosition pos = new ParsePosition(0);
            Number num = formatter.parse(value, pos);

            // If there was no error      and we used the whole string
            if (pos.getErrorIndex() == -1 && pos.getIndex() == value.length()) {
                if (num.doubleValue() >= Byte.MIN_VALUE &&
                    num.doubleValue() <= Byte.MAX_VALUE) {
                    result = new Byte(num.byteValue());
                }
            }
        }

        return result;
    }

    /**
     *  Checks if the value can safely be converted to a short primitive.
     *
     *@param  value  The value validation is being performed on.
     *@return the converted Short value.
     */
    public static Short formatShort(String value) {
        if (value == null) {
            return null;
        }

        try {
            return new Short(value);
        } catch (NumberFormatException e) {
            return null;
        }

    }

    /**
     *  Checks if the value can safely be converted to a short primitive.
     *
     *@param  value   The value validation is being performed on.
     *@param  locale  The locale to use to parse the number (system default if
     *      null)vv
     *@return the converted Short value.
     */
    public static Short formatShort(String value, Locale locale) {
        Short result = null;

        if (value != null) {
            NumberFormat formatter = null;
            if (locale != null) {
                formatter = NumberFormat.getNumberInstance(locale);
            } else {
                formatter = NumberFormat.getNumberInstance(Locale.getDefault());
            }
            formatter.setParseIntegerOnly(true);
            ParsePosition pos = new ParsePosition(0);
            Number num = formatter.parse(value, pos);

            // If there was no error      and we used the whole string
            if (pos.getErrorIndex() == -1 && pos.getIndex() == value.length()) {
                if (num.doubleValue() >= Short.MIN_VALUE &&
                    num.doubleValue() <= Short.MAX_VALUE) {
                    result = new Short(num.shortValue());
                }
            }
        }

        return result;
    }

    /**
     *  Checks if the value can safely be converted to a int primitive.
     *
     *@param  value  The value validation is being performed on.
     *@return the converted Integer value.
     */
    public static Integer formatInt(String value) {
        if (value == null) {
            return null;
        }

        try {
            return new Integer(value);
        } catch (NumberFormatException e) {
            return null;
        }

    }

    /**
     *  Checks if the value can safely be converted to an int primitive.
     *
     *@param  value   The value validation is being performed on.
     *@param  locale  The locale to use to parse the number (system default if
     *      null)
     *@return the converted Integer value.
     */
    public static Integer formatInt(String value, Locale locale) {
        Integer result = null;

        if (value != null) {
            NumberFormat formatter = null;
            if (locale != null) {
                formatter = NumberFormat.getNumberInstance(locale);
            } else {
                formatter = NumberFormat.getNumberInstance(Locale.getDefault());
            }
            formatter.setParseIntegerOnly(true);
            ParsePosition pos = new ParsePosition(0);
            Number num = formatter.parse(value, pos);

            // If there was no error      and we used the whole string
            if (pos.getErrorIndex() == -1 && pos.getIndex() == value.length()) {
                if (num.doubleValue() >= Integer.MIN_VALUE &&
                    num.doubleValue() <= Integer.MAX_VALUE) {
                    result = new Integer(num.intValue());
                }
            }
        }

        return result;
    }

    /**
     *  Checks if the value can safely be converted to a long primitive.
     *
     *@param  value  The value validation is being performed on.
     *@return the converted Long value.
     */
    public static Long formatLong(String value) {
        if (value == null) {
            return null;
        }

        try {
            return new Long(value);
        } catch (NumberFormatException e) {
            return null;
        }

    }

    /**
     *  Checks if the value can safely be converted to a long primitive.
     *
     *@param  value   The value validation is being performed on.
     *@param  locale  The locale to use to parse the number (system default if
     *      null)
     *@return the converted Long value.
     */
    public static Long formatLong(String value, Locale locale) {
        Long result = null;

        if (value != null) {
            NumberFormat formatter = null;
            if (locale != null) {
                formatter = NumberFormat.getNumberInstance(locale);
            } else {
                formatter = NumberFormat.getNumberInstance(Locale.getDefault());