Java tutorial
/* * 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.asual.summer.sample.domain; import static javax.persistence.GenerationType.IDENTITY; import java.io.File; import java.io.FileInputStream; import java.io.FileOutputStream; import java.io.IOException; import java.io.ObjectInputStream; import java.io.ObjectOutputStream; import java.io.Serializable; import java.net.URL; import java.util.List; import javax.persistence.Column; import javax.persistence.Entity; import javax.persistence.EntityManager; import javax.persistence.FetchType; import javax.persistence.GeneratedValue; import javax.persistence.Id; import javax.persistence.JoinColumn; import javax.persistence.JoinTable; import javax.persistence.Lob; import javax.persistence.ManyToMany; import javax.persistence.PersistenceContext; import javax.persistence.Table; import javax.validation.constraints.NotNull; import javax.validation.constraints.Size; import org.apache.commons.logging.Log; import org.apache.commons.logging.LogFactory; import org.hibernate.validator.constraints.NotEmpty; import org.springframework.beans.factory.annotation.Configurable; import org.springframework.transaction.annotation.Transactional; import org.springframework.web.multipart.MultipartFile; import com.asual.summer.core.util.StringUtils; /** * * @author Rostislav Hristov * */ @Configurable @Entity @Table public class Technology implements Serializable { private static final long serialVersionUID = 1L; private static final Log logger = LogFactory.getLog(Technology.class); @PersistenceContext private transient EntityManager entityManager; @Id @GeneratedValue(strategy = IDENTITY) @Column(unique = true, nullable = false) private Integer id; @Column(unique = true, nullable = false) private String value; @NotEmpty @Size(max = 128) @Column(length = 128) private String name; @Size(min = 32, max = 512) @Column(length = 512) private String description; @Size(max = 255) @Column private String version; @Column private URL homepage; @ManyToMany(fetch = FetchType.EAGER) @JoinTable(name = "technology_license", joinColumns = { @JoinColumn(name = "technology_id") }, inverseJoinColumns = { @JoinColumn(name = "license_id") }) private List<License> licenses; @NotNull @Column private Status status; @Column private boolean required; @Lob private Image image; public Technology() { } public Integer getId() { return id; } public void setId(Integer id) { this.id = id; } public String getValue() { return value; } public void setValue(String value) { this.value = value; } public String getName() { return name; } public void setName(String name) { if (name != null) { value = StringUtils.toUriPath(name); } this.name = name; } public String getDescription() { return description; } public void setDescription(String description) { this.description = description; } public String getVersion() { return version; } public void setVersion(String version) { this.version = version; } public URL getHomepage() { return homepage; } public void setHomepage(URL homepage) { this.homepage = homepage; } public List<License> getLicenses() { return licenses; } public void setLicenses(List<License> licenses) { this.licenses = licenses; } public Status getStatus() { return status; } public void setStatus(Status status) { this.status = status; } public boolean isRequired() { return required; } public void setRequired(boolean required) { this.required = required; } public Image getImage() { setImage(image); return image; } public void setImage(Image image) { if (image != null) { File file = new File(new File(System.getProperty("java.io.tmpdir")), value); try { FileOutputStream fos = new FileOutputStream(file); ObjectOutputStream oos = new ObjectOutputStream(fos); oos.writeObject(image); oos.flush(); fos.close(); } catch (IOException e) { logger.error(e.getMessage(), e); } } else if (value != null) { image = findImage(value); } this.image = image; } public int hashCode() { final int prime = 31; int result = 1; result = prime * result + ((value == null) ? 0 : value.hashCode()); return result; } public boolean equals(Object obj) { if (this == obj) return true; if (obj == null) return false; if (getClass() != obj.getClass()) return false; Technology other = (Technology) obj; if (value == null) { if (other.value != null) return false; } else if (!value.equals(other.value)) return false; return true; } @Transactional public void persist() { entityManager.persist(this); } @Transactional public Technology merge() { Technology merged = entityManager.merge(this); entityManager.flush(); return merged; } @Transactional public void remove() { if (entityManager.contains(this)) { entityManager.remove(this); } else { Technology attached = entityManager.find(this.getClass(), this.id); entityManager.remove(attached); } } @Transactional public void flush() { entityManager.flush(); } private static final EntityManager entityManager() { EntityManager em = new Technology().entityManager; if (em == null) { throw new IllegalStateException("Entity manager has not been injected."); } return em; } @SuppressWarnings("unchecked") public static Technology find(String value) { List<Technology> technologies = entityManager().createQuery("select o from Technology o where o.value = ?1") .setParameter(1, value).getResultList(); if (technologies.size() != 0) { return technologies.get(0); } return null; } public static Image findImage(String value) { if (value != null) { try { File file = new File(new File(System.getProperty("java.io.tmpdir")), value); if (file.exists()) { FileInputStream fis = new FileInputStream(file); ObjectInputStream ois = new ObjectInputStream(fis); return (Image) ois.readObject(); } } catch (Exception e) { logger.error(e.getMessage(), e); } } return null; } @SuppressWarnings("unchecked") public static List<Technology> list() { return entityManager().createQuery("select o from Technology o").getResultList(); } @SuppressWarnings("unchecked") public static List<Technology> list(int firstResult, int maxResults) { return entityManager().createQuery("select o from Technology o").setFirstResult(firstResult) .setMaxResults(maxResults).getResultList(); } public static class Image implements Serializable { private static final long serialVersionUID = 1L; private String value; private String contentType; private byte[] bytes; public Image(MultipartFile file) throws IOException { setValue(file.getOriginalFilename()); setContentType(file.getContentType()); setBytes(file.getBytes()); } public String getValue() { return value; } public void setValue(String value) { this.value = value; } public String getContentType() { return contentType; } public void setContentType(String contentType) { this.contentType = contentType; } public byte[] getBytes() { return bytes; } public void setBytes(byte[] bytes) { this.bytes = bytes; } } }