com.trailmagic.image.ui.ImageTag.java Source code

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Here is the source code for com.trailmagic.image.ui.ImageTag.java

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/*
 * Copyright (c) 2006 Oliver Stewart.  All Rights Reserved.
 *
 * This file is free software; you can redistribute it and/or modify
 * it under the terms of the GNU General Public License as published by
 * the Free Software Foundation; either version 2, or (at your option)
 * any later version.
 *
 * This file is distributed in the hope that it will be useful,
 * but WITHOUT ANY WARRANTY; without even the implied warranty of
 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
 * GNU General Public License for more details.
 */
package com.trailmagic.image.ui;

import org.apache.taglibs.standard.tag.common.core.Util;

import java.io.IOException;
import javax.servlet.http.HttpServletRequest;
import javax.servlet.http.HttpSession;
import javax.servlet.jsp.JspException;
import javax.servlet.jsp.tagext.TagSupport;
import org.springframework.web.context.WebApplicationContext;
import org.springframework.web.context.support.WebApplicationContextUtils;
/*
import javax.servlet.jsp.el.ExpressionEvaluator;
import javax.servlet.jsp.el.VariableResolver;
*/
import com.trailmagic.user.*;
import com.trailmagic.image.*;

public class ImageTag extends TagSupport {
    private Image m_image;
    private String m_sizeLabel;
    private String m_alt;
    private String m_cssClass;

    private static final String USER_ATTR = "user";
    private static final String DEFAULT_LABEL_ATTR = "defaultLabel";
    private static final String SIZE_ATTR = "size";
    private static final String LABEL_ATTR = "label";

    public int doStartTag() throws JspException {
        StringBuffer html = new StringBuffer();
        ImageManifestation mf;

        try {
            HttpServletRequest req = (HttpServletRequest) pageContext.getRequest();
            // XXX: maybe this should be a parameter of the tag instead?

            // XXX: this is sort of a kludge for setting a default label
            String defaultLabel = req.getParameter(DEFAULT_LABEL_ATTR);
            HttpSession session = req.getSession();
            if (defaultLabel != null) {
                session.setAttribute(DEFAULT_LABEL_ATTR, defaultLabel);
            }

            // XXX: end kludge

            String size = req.getParameter(SIZE_ATTR);
            String originalp = req.getParameter("original");
            if (size != null) {
                mf = WebSupport.getMFBySize(m_image, Integer.parseInt(size), Boolean.parseBoolean(originalp));
            } else {
                // get label by precedence: req param, tag spec, sess attr
                String label = req.getParameter(LABEL_ATTR);
                if (label == null) {
                    label = m_sizeLabel;
                }
                if (label == null) {
                    label = (String) session.getAttribute(DEFAULT_LABEL_ATTR);
                }
                if (label != null) {
                    mf = WebSupport.getMFByLabel(m_image, label);
                } else {
                    mf = WebSupport.getDefaultMF((User) pageContext.findAttribute(USER_ATTR), m_image);
                }
            }

            if (mf != null) {
                // XXX: resume kludge
                pageContext.setAttribute("currentLabel", getLabel(mf));
                // XXX: end kludge
                // XXX: end kludge
                html.append("<img src=\"");

                //XXX: yeek?
                /*
                LinkHelper helper =
                new LinkHelper((HttpServletRequest)pageContext.getRequest());
                */
                WebApplicationContext ctx = WebApplicationContextUtils
                        .getRequiredWebApplicationContext(pageContext.getServletContext());
                LinkHelper helper = (LinkHelper) ctx.getBean("linkHelper");

                html.append(helper.getImageMFUrl((HttpServletRequest) pageContext.getRequest(), mf));
                html.append("\" height=\"");
                html.append(mf.getHeight());
                html.append("\" width=\"");
                html.append(mf.getWidth());
                html.append("\" alt=\"");
                if (m_alt != null) {
                    html.append(m_alt);
                } else if (m_image.getCaption() != null) {
                    html.append(Util.escapeXml(m_image.getCaption()));
                } else {
                    html.append(Util.escapeXml(m_image.getDisplayName()));
                }

                html.append("\" class=\"");
                if (mf.getWidth() > mf.getHeight()) {
                    html.append("landscape");
                } else {
                    html.append("portrait");
                }
                if (m_cssClass != null) {
                    html.append(" ");
                    html.append(m_cssClass);
                }

                html.append("\"/>");
            } else {
                html.append("No manifestations found for the specified " + "image.");
            }
            pageContext.getOut().write(html.toString());
            return SKIP_BODY;
        } catch (IOException e) {
            throw new JspException(e);
        }
    }

    public void setImage(Image image) {
        m_image = image;
    }

    public Image getImage() {
        return m_image;
    }

    public void setSizeLabel(String label) {
        m_sizeLabel = label;
    }

    public String getSizeLabel() {
        return m_sizeLabel;
    }

    public void setAlt(String alt) {
        m_alt = alt;
    }

    public String getAlt() {
        return m_alt;
    }

    public void setCssClass(String cssClass) {
        m_cssClass = cssClass;
    }

    public String getCssClass() {
        return m_cssClass;
    }

    private String getLabel(ImageManifestation mf) {
        int area = mf.getArea();
        int distance = Integer.MAX_VALUE;
        int newDistance;
        String label = "small";

        newDistance = Math.abs(area - 192 * 128);
        if (newDistance < distance) {
            label = "thumbnail";
            distance = newDistance;
        }
        newDistance = Math.abs(area - 384 * 256);
        if (newDistance < distance) {
            label = "small";
            distance = newDistance;
        }
        newDistance = Math.abs(area - 768 * 512);
        if (newDistance < distance) {
            label = "medium";
            distance = newDistance;
        }
        newDistance = Math.abs(area - 1536 * 1024);
        if (newDistance < distance) {
            label = "large";
            distance = newDistance;
        }
        newDistance = Math.abs(area - 3072 * 2048);
        if (newDistance < distance) {
            label = "huge";
        }
        return label;
    }
}