org.drools.brms.client.modeldriven.ui.DSLSentenceWidget.java Source code

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Here is the source code for org.drools.brms.client.modeldriven.ui.DSLSentenceWidget.java

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package org.drools.brms.client.modeldriven.ui;
/*
 * Copyright 2005 JBoss Inc
 * 
 * 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.
 */

import java.util.ArrayList;
import java.util.Iterator;
import java.util.List;

import org.drools.brms.client.common.DirtyableComposite;
import org.drools.brms.client.common.DirtyableHorizontalPane;
import org.drools.brms.client.modeldriven.brl.DSLSentence;

import com.google.gwt.user.client.ui.ChangeListener;
import com.google.gwt.user.client.ui.Composite;
import com.google.gwt.user.client.ui.HTML;
import com.google.gwt.user.client.ui.HorizontalPanel;
import com.google.gwt.user.client.ui.Label;
import com.google.gwt.user.client.ui.TextBox;
import com.google.gwt.user.client.ui.Widget;

/**
 * This displays a widget to edit a DSL sentence.
 * @author Michael Neale
 */
public class DSLSentenceWidget extends DirtyableComposite {

    private final DirtyableHorizontalPane horiz;
    private final List widgets;
    private final DSLSentence sentence;

    public DSLSentenceWidget(DSLSentence sentence) {
        horiz = new DirtyableHorizontalPane();
        widgets = new ArrayList();
        this.sentence = sentence;
        init();
    }

    private void init() {
        makeWidgets(this.sentence.sentence);
        initWidget(this.horiz);
    }

    /** 
     * This will take a DSL line item, and split it into widget thingamies for displaying.
     * One day, if this is too complex, this will have to be done on the server side.
     */
    public void makeWidgets(String dslLine) {

        char[] chars = dslLine.toCharArray();
        FieldEditor currentBox = null;
        Label currentLabel = null;
        for (int i = 0; i < chars.length; i++) {
            char c = chars[i];
            if (c == '{') {
                currentLabel = null;
                currentBox = new FieldEditor();
                addWidget(currentBox);

            } else if (c == '}') {
                currentBox.setVisibleLength(currentBox.getText().length() + 1);
                currentBox = null;
            } else {
                if (currentBox == null && currentLabel == null) {
                    currentLabel = new Label();
                    addWidget(currentLabel);
                }
                if (currentLabel != null) {
                    currentLabel.setText(currentLabel.getText() + c);
                } else if (currentBox != null) {
                    currentBox.setText(currentBox.getText() + c);
                }

            }
        }

    }

    private void addWidget(Widget currentBox) {
        this.horiz.add(currentBox);
        widgets.add(currentBox);
    }

    /**
     * This will go through the widgets and build up a sentence.
     */
    protected void updateSentence() {
        String newSentence = "";
        for (Iterator iter = widgets.iterator(); iter.hasNext();) {
            Widget wid = (Widget) iter.next();
            if (wid instanceof Label) {
                newSentence = newSentence + ((Label) wid).getText();
            } else if (wid instanceof FieldEditor) {
                newSentence = newSentence + " {" + ((FieldEditor) wid).getText() + "} ";
            }
        }
        this.sentence.sentence = newSentence.trim();

    }

    class FieldEditor extends DirtyableComposite {

        private TextBox box;
        private HorizontalPanel panel = new HorizontalPanel();

        public FieldEditor() {
            box = new TextBox();
            //box.setStyleName( "dsl-field-TextBox" );

            panel.add(new HTML("&nbsp;"));
            panel.add(box);
            panel.add(new HTML("&nbsp;"));

            box.addChangeListener(new ChangeListener() {
                public void onChange(Widget w) {
                    updateSentence();
                    makeDirty();
                }
            });

            initWidget(panel);
        }

        public void setText(String t) {
            box.setText(t);
        }

        public void setVisibleLength(int l) {
            box.setVisibleLength(l);
        }

        public String getText() {
            return box.getText();
        }
    }

    public boolean isDirty() {
        return horiz.hasDirty();
    }

}