localdomain.localhost.ProductImageUploadServlet.java Source code

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Here is the source code for localdomain.localhost.ProductImageUploadServlet.java

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/*
 * Copyright 2010-2013, the original author or authors
 *
 * 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 localdomain.localhost;

import com.amazonaws.services.s3.model.ObjectMetadata;
import localdomain.localhost.domain.Product;
import org.slf4j.Logger;
import org.slf4j.LoggerFactory;

import javax.annotation.Nonnull;
import javax.persistence.EntityManager;
import javax.persistence.EntityManagerFactory;
import javax.servlet.ServletConfig;
import javax.servlet.ServletContext;
import javax.servlet.ServletException;
import javax.servlet.annotation.MultipartConfig;
import javax.servlet.annotation.WebServlet;
import javax.servlet.http.HttpServlet;
import javax.servlet.http.HttpServletRequest;
import javax.servlet.http.HttpServletResponse;
import java.io.IOException;
import java.io.InputStream;
import java.util.concurrent.TimeUnit;

@WebServlet(value = "/product/upload", loadOnStartup = 2)
@MultipartConfig
public class ProductImageUploadServlet extends HttpServlet {

    protected final Logger logger = LoggerFactory.getLogger(getClass());
    @Nonnull
    private EntityManagerFactory emf;

    @Override
    public void init(ServletConfig config) throws ServletException {
        super.init(config);
        emf = (EntityManagerFactory) config.getServletContext().getAttribute(EntityManagerFactory.class.getName());
        if (emf == null)
            throw new ServletException("JPA EntityManagerFactory not found in ServletContext");

        logger.debug("Servlet initialized, JPA EntityManagerFactory loaded");
    }

    @Override
    protected void doPost(HttpServletRequest request, HttpServletResponse response)
            throws ServletException, IOException {
        try {
            String itemName = request.getParameter("productName");
            String credits = request.getParameter("imageCredits");

            InputStream is = request.getPart("imageFile").getInputStream();
            ObjectMetadata objectMetadata = new ObjectMetadata();
            objectMetadata.setContentLength(request.getPart("imageFile").getSize());
            objectMetadata.setContentType(request.getPart("imageFile").getContentType());
            objectMetadata.setCacheControl("public, max-age=" + TimeUnit.SECONDS.convert(365, TimeUnit.DAYS));

            String imageName = getFileNameFromHeader(request.getPart("imageFile").getHeader("content-disposition"));

            ServletContext context = request.getSession().getServletContext();
            AmazonS3Resources s3Resources = (AmazonS3Resources) context
                    .getAttribute(AmazonS3Resources.class.getName());

            String imageUrl = s3Resources.uploadImage(is, objectMetadata, imageName);

            EntityManager em = emf.createEntityManager();

            em.getTransaction().begin();
            em.persist(new Product(itemName, imageUrl, credits));
            em.getTransaction().commit();

            response.sendRedirect(request.getContextPath() + "/product/list");
        } catch (Exception e) {
            request.setAttribute("throwable", e);
            request.getRequestDispatcher("/WEB-INF/jsp/products.jsp").forward(request, response);
        }

    }

    @Nonnull
    private String getFileNameFromHeader(@Nonnull String header) throws IllegalArgumentException {
        String fileName = null;

        for (String onePiece : header.split(";")) {
            if (onePiece.contains("filename=")) {
                String myPieces[] = onePiece.split("=");
                fileName = myPieces[1].replaceAll("\"", "").trim();
            }
        }
        if (null == fileName)
            throw new IllegalArgumentException("The Header provided is not valid");
        return fileName;
    }
}