DatabaseCreationFieldValidator.java

/*
 * Copyright (C) 2012 The Android Open Source Project
 *
 * 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.motorolamobility.studio.android.db.core.ui.wizards.createdb;

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

import org.eclipse.jface.dialogs.IInputValidator;
import org.eclipse.osgi.util.NLS;

import com.motorolamobility.studio.android.db.core.i18n.DbCoreNLS;

/**
 * This class represents a database name validator. The name must not
 * not already exists in the Database View tree and must follow a certain pattern.
 */
public class DatabaseCreationFieldValidator implements IInputValidator
{

    /**
     * The regular expression pattern used to validate the database name provided by the user
     */
    private static final String VALIDATOR_PATTERN = "[a-zA-Z0-9 ._-]+(.db)?"; //$NON-NLS-1$

    /**
     * The extension of the database files at the device
     */
    private static final String DB_EXTENSION = ".db"; //$NON-NLS-1$

    /**
     * Expression pattern used to validate the database name provided by the user
     */
    private final Pattern pattern = Pattern.compile(VALIDATOR_PATTERN);

    private final List<String> alreadyAvailableDbs;

    public DatabaseCreationFieldValidator(final List<String> alreadyAvailableDbs)
    {
        this.alreadyAvailableDbs = alreadyAvailableDbs;
    }

    /*
     * (non-Javadoc)
     * @see org.eclipse.jface.dialogs.IInputValidator#isValid(java.lang.String)
     */
    public String isValid(String newText)
    {
        String msg = null;
        Matcher patternMatcher = pattern.matcher(newText);
        if (!patternMatcher.matches())
        {
            msg = DbCoreNLS.DatabaseCreationFieldValidator_ValidChars;
        }
        else
        // check whether the database already exists
        {
            String dbFileName = newText + DB_EXTENSION;
            if (alreadyAvailableDbs.contains(dbFileName))
            {
                msg =
                        NLS.bind(DbCoreNLS.DatabaseCreationFieldValidator_DB_Already_Exists_Msg,
                                dbFileName);
            }
        }

        return msg;
    }
}