image resize java

PhotoUtils.java

package com.blogspot.na5cent.utils;

import java.awt.AlphaComposite;
import java.awt.Graphics2D;
import java.awt.RenderingHints;
import java.awt.image.BufferedImage;

/**
 *
 * @author redcrow
 */
public class PhotoUtils {

    private static final int DEFAULT_TYPE = 5;

    public static BufferedImage resize(BufferedImage image, int newWidth, int newHeight) {
        int oldWidth = image.getWidth();
        int oldHeight = image.getHeight();

        if (oldHeight < newHeight || oldWidth < newWidth) {
            newHeight = oldHeight;
            newWidth = oldWidth;
        }else{
            float percentWidth = newWidth / (float) oldWidth;
            float percentHeight = newHeight / (float) oldHeight;

            if (newWidth == 0) {
                newWidth = (int) (percentHeight * oldWidth);
            }

            if (newHeight == 0) {
                newHeight = (int) (percentWidth * oldHeight);
            }
        }

        BufferedImage resized = new BufferedImage(newWidth, newHeight, DEFAULT_TYPE);
        Graphics2D g = resized.createGraphics();
        g.drawImage(image, 0, 0, newWidth, newHeight, null);
        g.dispose();

        return resized;
    }
}

Example to use 

PhotoService.java (Spring MVC : controller)

package com.blogspot.na5cent.service;

import com.google.common.io.ByteStreams;
import java.awt.image.BufferedImage;
import java.io.ByteArrayInputStream;
import java.io.ByteArrayOutputStream;
import java.io.File;
import java.io.IOException;
import java.io.InputStream;
import javax.imageio.ImageIO;
import javax.servlet.http.HttpServletRequest;
import javax.servlet.http.HttpServletResponse;
import org.springframework.stereotype.Controller;
import org.springframework.web.bind.annotation.RequestMapping;
import org.springframework.web.bind.annotation.RequestMethod;
import org.springframework.web.bind.annotation.ResponseBody;
import com.blogspot.na5cent.utils.PhotoUtils;
import com.blogspot.na5cent.configs.FileConfigs;

/**
 *
 * @author redcrow
 */
@Controller
public class PhotoService {

    private static final File DIRECTORY_UPLOAD = FileConfigs.DIRECTORY_UPLOAD;

    @RequestMapping(value = "/service/photo", method = RequestMethod.GET)
    @ResponseBody
    public String getFile(HttpServletRequest request, HttpServletResponse response) throws IOException {
        //
        String fileName = request.getParameter("name");
        String width = request.getParameter("width");
        String height = request.getParameter("height");
        String type = request.getServletContext().getMimeType(fileName);

        int widthInt = (width == null) ? 0 : Integer.parseInt(width);
        int heightInt = (height == null) ? 0 : Integer.parseInt(height);

        if (widthInt == 0 && heightInt == 0) {
            response.sendError(HttpServletResponse.SC_NOT_FOUND); // 404.          
            return null;
        }

        File file = new File(DIRECTORY_UPLOAD, fileName);
        BufferedImage image;
        try {
            image = ImageIO.read(file);
        } catch (Exception ex) {
            response.sendError(HttpServletResponse.SC_NOT_FOUND); // 404.          
            return null;
        }
        
        image = PhotoUtils.resize(image, widthInt, heightInt); //*****

        response.reset();
        response.setBufferSize(1024);
        response.setContentType(type);
        response.setHeader("Content-Disposition", "inline; filename=\"" + fileName + "\"");

        InputStream inputStream = null;
        ByteArrayOutputStream baos = null;
        try {
            baos = new ByteArrayOutputStream();
            ImageIO.write(image, "png", baos);
            inputStream = new ByteArrayInputStream(baos.toByteArray());
            response.setHeader("Content-Length", String.valueOf(baos.size()));
            ByteStreams.copy(inputStream, response.getOutputStream());
        } finally {
            if (inputStream != null) {
                inputStream.close();
            }

            if (baos != null) {
                baos.close();
            }
        }

        return null;
    }
}

html

<!-- image -->
<img src="http://na5cent.blogspot.com/service/photo?name=duck.png&width=200"/>
<!-- image -->

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