[問題] 關於 reflection 問題

看板java作者daden (出門去睡覺)時間8年前 (2016/11/15 16:00)推噓0(0推 0噓 3→)

留言3則, 3人參與討論串1/1

各位前輩好小弟目前有個問題，目前我有一個作法是想自動產生 HQL 的語法但是卡在 reflection 的作法，所以想上來請教一下大家，請問要如何將 id 部份的 fields 和 values 取出這部份不太知道要如何做，請前輩們幫解題一下，謝謝以下為程式碼 User.java --------------------------------------------------------- @Entity @Table(name = "user") public class User implements Serializable { @EmbeddedId UserId id; @NotEmpty @Column(name = "user_name", nullable = false) private String userName; @NotEmpty @Column(name = "password", nullable = false) private String password; @Column(name = "status") private String status; @Column(name = "email", nullable = false) private String email; @NotEmpty @Column(name = "registerTime", nullable = false) private String registerTime; @NotEmpty @Column(name = "lastActiveTime", nullable = false) private String lastActiveTime; .......getters setters ============================================================ UserId.java ------------------------------------------------------------ @Embeddable public class UserId implements Serializable { @Column(name = "user_Id") public Integer userId; @Column(name = "account") public String account; .......getters setters ============================================================= Test.java ------------------------------------------------------------- public class Test { public static void main(String[] args) throws Exception { User user = new User(); UserId id = new UserId(); user.setEmail("weqqr"); user.setStatus("2"); user.setPassword("eeeeee"); id.setAccount("wwwwwerrr"); id.setUserId(2244); user.setId(id); Test test = new Test(); System.out.println(test.genUpdateHql(user, null, null)); } private String genUpdateHql(Object entity, Map<String, Object> argMap, String condition) throws Exception { BeanInfo beanInfo = Introspector.getBeanInfo(entity.getClass()); PropertyDescriptor[] descriptors = beanInfo.getPropertyDescriptors(); String entityName = entity.getClass().getSimpleName(); StringBuilder hqlStr = new StringBuilder(); hqlStr.append("UPDATE " + entityName + " " + entityName + " SET "); for (int i = 0; i < descriptors.length; i++) { String propName = descriptors[i].getName(); Class<?> propType = descriptors[i].getPropertyType(); Object value = PropertyUtils.getProperty(entity, propName); if (!propName.equals("class") && null != value) { if (propType.getSimpleName().equals("Integer") || propType.getSimpleName().equals("int")) { hqlStr.append(entityName + "." + propName + "=" + value + ""); } else if (propType.getSimpleName().equals("String")) { hqlStr.append(entityName + "." + propName + "=" + "'" + value + "'"); } else if (propName.equals("id")) { } hqlStr.append(","); } } hqlStr = hqlStr.deleteCharAt(hqlStr.length() - 1); hqlStr = hqlStr.append(" WHERE User.id.userId=:userId AND User.id.account=:account"); return hqlStr.toString(); } } -- ※ 發信站: 批踢踢實業坊(ptt.cc), 來自: 49.218.51.133 ※ 文章網址: https://www.ptt.cc/bbs/java/M.1479196850.A.57B.html