Field.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.motorola.studio.android.db.wizards.model;

import com.motorola.studio.android.codeutils.i18n.CodeUtilsNLS;

/**
 * This class abstracts a field in a database table. 
 * */
public class Field
{
    /**
     * A primary key may be set to be updated incrementally, decrementally or none.
     * */
    public enum PrimaryKeyBehaviour
    {
        NONE, INCREMENTAL, DECREMENTAL
    };

    private String type;

    private String name;

    private String defaultValue;

    private boolean isPrimary;

    private PrimaryKeyBehaviour primaryKeyBehaviour;

    /**
     * @return The behavior of the primary key as described in {@link PrimaryKeyBehaviour}.
     * */
    public PrimaryKeyBehaviour getPrimaryKeyBehaviour()
    {
        return primaryKeyBehaviour;
    }

    /**
     * Set the primary key behavior as described in {@link PrimaryKeyBehaviour}.
     * */
    public void setPrimaryKeyBehaviour(PrimaryKeyBehaviour primaryKeyBehaviour)
    {
        this.primaryKeyBehaviour = primaryKeyBehaviour;
    }

    /**
     * Constructor that initializes the field name.
     * */
    public Field(String name)
    {
        this.name = name;
    }

    /**
     * @return field type.
     * */
    public String getType()
    {
        return type;
    }

    public void setType(String type)
    {
        this.type = type;
    }

    /**
     * @return field name.
     * */
    public String getName()
    {
        return name;
    }

    public void setName(String name)
    {
        this.name = name;
    }

    /**
     * @return The default value used to fill in the field when it has no value in insert statements.
     * */
    public String getDefaultValue()
    {
        return defaultValue;
    }

    public void setDefaultValue(String defaultValue)
    {
        this.defaultValue = defaultValue;
    }

    /**
     * @return True if this field belongs to the primary key set. Otherwise, returns false.
     * */
    public boolean isPrimary()
    {
        return isPrimary;
    }

    public void setPrimary(boolean isPrimary)
    {
        this.isPrimary = isPrimary;
    }

    /**
     * @return 
     * <ul>
     *  <li>empty string, if {@link PrimaryKeyBehaviour} is set to {@link PrimaryKeyBehaviour#NONE}.</li>
     *  <li>ASC, if {@link PrimaryKeyBehaviour} is set to {@link PrimaryKeyBehaviour#INCREMENTAL}.</li>
     *  <li>DESC, if {@link PrimaryKeyBehaviour} is set to {@link PrimaryKeyBehaviour#DECREMENTAL}.</li>
     * </ul>
     * */
    public String getKeyBehaviourQuery()
    {
        String[] query =
        {
                "", " ASC", " DESC" //$NON-NLS-1$ //$NON-NLS-2$ //$NON-NLS-3$
        };

        return query[getPrimaryKeyBehaviour().ordinal()];

    }

    /**
     * @return An string describing field property error and {@code null} if there are no errors. 
     * */
    public String getErrorMessage()
    {
        String message = null;

        if (!type.equals("INTEGER") && !type.equals("REAL") //$NON-NLS-1$ //$NON-NLS-2$
                && !primaryKeyBehaviour.equals(PrimaryKeyBehaviour.NONE))
        {
            message = CodeUtilsNLS.Field_ErrorAutoIncrementNotAllowed;
        }

        // Validate name to don't use sqlite keywords
        if ((message == null) && !Table.validateName(getName()))
        {

            message = CodeUtilsNLS.AddTableFieldDialog_InvalidName + getName();
        }

        return message;
    }

}