标签:des style blog http io ar color os 使用
今天笔记主要是记录笔记,以及代码:
criteria:
创建查询接口:createCriteria(class)
查询条件接口:add(各种条件);
Restrictions 提供了设置参数的各种接口
逻辑运算 not or and
字符串模式匹配 like ilike
范围运算 in not in between between and
比较运算 eq/le/lt.....
集合运算 isNotEmpty
可以链式编程
List grades=session.createCriteria(Grade.class)
.add(Restrictions.or(Restrictions.eq("gradename", "一年级"), Restrictions.le("gradeid", 3)))
.list();
关于各种方法的使用,代码中都有注释
注解配置:
可以在启动AnnotationConfiguration时在数据库创建配置的表
注解:
需要引入四个包:
1 package entity; 2 import java.io.Serializable; 3 import javax.persistence.*; 4 5 @Entity 6 @Table(name="test_g") 7 public class TestNoteGrade implements Serializable{ 8 private Integer id ; 9 private String name; 10 @Id 11 @GeneratedValue(strategy=GenerationType.SEQUENCE,generator="seq_grade") 12 @SequenceGenerator(name="seq_grade",sequenceName="seq_gradeid",allocationSize=1,initialValue=1) 13 public Integer getId() { 14 return id; 15 } 16 17 public void setId(Integer id) { 18 this.id = id; 19 } 20 @Basic 21 public String getName() { 22 return name; 23 } 24 public void setName(String name) { 25 this.name = name; 26 } 27 28 29 30 31 }
在hibernate中需要配置 mapping:
<mapping class="entity.TestNoteGrade"/>
还有种生成实体类与映射文件的方法:
反推(用myeclipse来操作)
java 测试代码:
1 package test4Criteria; 2 3 import java.util.ArrayList; 4 import java.util.List; 5 import java.util.Set; 6 7 import junit.framework.TestCase; 8 import org.hibernate.Criteria; 9 import org.hibernate.Session; 10 import org.hibernate.cfg.AnnotationConfiguration; 11 import org.hibernate.criterion.Criterion; 12 import org.hibernate.criterion.DetachedCriteria; 13 import org.hibernate.criterion.Order; 14 import org.hibernate.criterion.Projections; 15 import org.hibernate.criterion.Property; 16 import org.hibernate.criterion.Restrictions; 17 18 import entity.Grade; 19 import entity.Student; 20 import entity.TrStudent; 21 22 import util.HibernateUtil; 23 24 public class Criterion01 extends TestCase{ 25 Session session=null; 26 27 28 29 /** 30 * critertion 查询 31 */ 32 public void testCriterion1(){ 33 try { 34 session=HibernateUtil.currentSession(); 35 session.beginTransaction(); 36 //查询整个类 37 List grade=session.createCriteria(Grade.class).list(); 38 for(int i=0;i<grade.size();i++){ 39 Grade gra=(Grade)grade.get(i); 40 System.out.println(gra); 41 42 } 43 44 45 } catch (Exception e) { 46 // TODO: handle exception 47 e.printStackTrace(); 48 }finally{ 49 HibernateUtil.closeSession(); 50 } 51 try { 52 session=HibernateUtil.currentSession(); 53 session.beginTransaction(); 54 //查询指定值 55 List grade=session.createCriteria(Grade.class)// 56 .add(Restrictions.eq("gradename","一年级"))// 57 .list(); 58 for(int i=0;i<grade.size();i++){ 59 Grade gra=(Grade)grade.get(i); 60 System.out.println(gra); 61 62 } 63 64 65 } catch (Exception e) { 66 // TODO: handle exception 67 e.printStackTrace(); 68 }finally{ 69 HibernateUtil.closeSession(); 70 } 71 72 } 73 /** 74 * 比较运算 75 */ 76 public void testCriterion2(){ 77 try { 78 session=HibernateUtil.currentSession(); 79 session.beginTransaction(); 80 //大于条件 81 List grades=session.createCriteria(Grade.class).add(Restrictions.gt("gradeid", 2)).list(); 82 83 for(int i=0;i<grades.size();i++){ 84 System.out.println((Grade)grades.get(i)); 85 86 } 87 } catch (Exception e) { 88 // TODO: handle exception 89 e.printStackTrace(); 90 }finally{ 91 HibernateUtil.closeSession(); 92 93 } 94 System.out.println("---大于等于条件--------------------"); 95 try { 96 session=HibernateUtil.currentSession(); 97 session.beginTransaction(); 98 //大于等于条件 99 List grades=session.createCriteria(Grade.class).add(Restrictions.ge("gradeid", 2)).list(); 100 101 for(int i=0;i<grades.size();i++){ 102 System.out.println((Grade)grades.get(i)); 103 104 } 105 } catch (Exception e) { 106 // TODO: handle exception 107 e.printStackTrace(); 108 }finally{ 109 HibernateUtil.closeSession(); 110 111 } 112 113 System.out.println("---小于等于条件--------------------"); 114 try { 115 session=HibernateUtil.currentSession(); 116 session.beginTransaction(); 117 //大于等于条件 118 List grades=session.createCriteria(Grade.class).add(Restrictions.le("gradeid", 2)).list(); 119 120 for(int i=0;i<grades.size();i++){ 121 System.out.println((Grade)grades.get(i)); 122 123 } 124 } catch (Exception e) { 125 // TODO: handle exception 126 e.printStackTrace(); 127 }finally{ 128 HibernateUtil.closeSession(); 129 130 } 131 System.out.println("---等于空--------------------"); 132 try { 133 session=HibernateUtil.currentSession(); 134 session.beginTransaction(); 135 //大于等于条件 136 List grades=session.createCriteria(Grade.class).add(Restrictions.isNull("gradeid")).list(); 137 138 for(int i=0;i<grades.size();i++){ 139 System.out.println((Grade)grades.get(i)); 140 141 } 142 } catch (Exception e) { 143 // TODO: handle exception 144 e.printStackTrace(); 145 }finally{ 146 HibernateUtil.closeSession(); 147 148 } 149 150 } 151 /** 152 * 范围运算 153 */ 154 public void testCriterion3(){ 155 try { 156 session=HibernateUtil.currentSession(); 157 session.beginTransaction(); 158 Object[] obj={1,2,3}; 159 //in 160 List grades=session.createCriteria(Grade.class)// 161 .add(Restrictions.in("gradeid",obj))// 162 .list(); 163 for(int i=0;i<grades.size();i++){ 164 System.out.println((Grade)grades.get(i)); 165 166 } 167 } catch (Exception e) { 168 // TODO: handle exception 169 e.printStackTrace(); 170 } 171 finally{ 172 HibernateUtil.closeSession(); 173 174 } 175 System.out.println("-----not--in------"); 176 try { 177 session=HibernateUtil.currentSession(); 178 session.beginTransaction(); 179 Object[] obj={1,2,3}; 180 //in 181 List grades=session.createCriteria(Grade.class)// 182 .add(Restrictions.not(Restrictions.in("gradeid",obj)))// 183 .list(); 184 for(int i=0;i<grades.size();i++){ 185 System.out.println((Grade)grades.get(i)); 186 187 } 188 } catch (Exception e) { 189 // TODO: handle exception 190 e.printStackTrace(); 191 } 192 finally{ 193 HibernateUtil.closeSession(); 194 195 } 196 197 System.out.println("--not-between- and--"); 198 try { 199 session=HibernateUtil.currentSession(); 200 session.beginTransaction(); 201 Object[] obj={1,2,3}; 202 //in 203 List grades=session.createCriteria(Grade.class)// 204 .add(Restrictions.not(Restrictions.between("gradeid",1,3)))// 205 .list(); 206 for(int i=0;i<grades.size();i++){ 207 System.out.println((Grade)grades.get(i)); 208 209 } 210 } catch (Exception e) { 211 // TODO: handle exception 212 e.printStackTrace(); 213 } 214 finally{ 215 HibernateUtil.closeSession(); 216 217 } 218 219 System.out.println("---between- and--"); 220 try { 221 session=HibernateUtil.currentSession(); 222 session.beginTransaction(); 223 Object[] obj={1,2,3}; 224 //in 225 List grades=session.createCriteria(Grade.class)// 226 .add(Restrictions.between("gradeid",1,3))// 227 .list(); 228 for(int i=0;i<grades.size();i++){ 229 System.out.println((Grade)grades.get(i)); 230 231 } 232 } catch (Exception e) { 233 // TODO: handle exception 234 e.printStackTrace(); 235 } 236 finally{ 237 HibernateUtil.closeSession(); 238 239 } 240 } 241 242 /** 243 * 字符串模式匹配 like ilike 244 */ 245 public void testCriterion4(){ 246 try { 247 session=HibernateUtil.currentSession(); 248 session.beginTransaction(); 249 String scase="ab"; 250 List student=session.createCriteria(Student.class).add(Restrictions.like("name", "%"+scase+"%")).list(); 251 for(int i=0;i<student.size();i++){ 252 Student stu=(Student)student.get(i); 253 String name=stu.getName(); 254 System.out.print(name.substring(0, name.indexOf(scase))); 255 System.err.print(name.substring(name.indexOf(scase),(name.indexOf(scase)+scase.length()))); 256 if(name.indexOf(scase)==name.length()-scase.length()){ 257 System.out.println(""); 258 259 } 260 System.out.println(name.substring(name.indexOf(scase)+scase.length(),name.length())); 261 262 } 263 264 } catch (Exception e) { 265 // TODO: handle exception 266 }finally{ 267 HibernateUtil.closeSession(); 268 269 } 270 System.out.println("------ilike----------"); 271 try { 272 session=HibernateUtil.currentSession(); 273 session.beginTransaction(); 274 String scase="eli"; 275 List student=session.createCriteria(Student.class).add(Restrictions.ilike("name", "%"+scase+"%")).list(); 276 for(int i=0;i<student.size();i++){ 277 Student stu=(Student)student.get(i); 278 String name=stu.getName().toLowerCase(); 279 System.out.print(name.substring(0, name.indexOf(scase))); 280 System.err.print(name.substring(name.indexOf(scase),(name.indexOf(scase)+scase.length()))); 281 if(name.indexOf(scase)==name.length()-scase.length()){ 282 System.out.println(""); 283 284 } 285 System.out.println(name.substring(name.indexOf(scase)+scase.length(),name.length())); 286 287 } 288 } catch (Exception e) { 289 // TODO: handle exception 290 }finally{ 291 HibernateUtil.closeSession(); 292 293 } 294 } 295 /** 296 * 逻辑运算 297 */ 298 public void testCriterion5(){ 299 try { 300 session=HibernateUtil.currentSession(); 301 session.beginTransaction(); 302 List grades=session.createCriteria(Grade.class).add(Restrictions.and(Restrictions.eq("gradename", "一年级"), Restrictions.le("gradeid", 5))).list(); 303 for(int i=0;i<grades.size();i++){ 304 System.out.println(grades.get(i)); 305 306 } 307 } catch (Exception e) { 308 // TODO: handle exception 309 e.printStackTrace(); 310 }finally{ 311 HibernateUtil.closeSession(); 312 313 } 314 System.out.println("-------or-----------"); 315 try { 316 session=HibernateUtil.currentSession(); 317 session.beginTransaction(); 318 List grades=session.createCriteria(Grade.class).add(Restrictions.or(Restrictions.eq("gradename", "一年级"), Restrictions.le("gradeid", 3))).list(); 319 for(int i=0;i<grades.size();i++){ 320 System.out.println(grades.get(i)); 321 322 } 323 } catch (Exception e) { 324 // TODO: handle exception 325 e.printStackTrace(); 326 }finally{ 327 HibernateUtil.closeSession(); 328 329 } 330 System.out.println("-------not-----------"); 331 try { 332 session=HibernateUtil.currentSession(); 333 session.beginTransaction(); 334 List grades=session.createCriteria(Grade.class).add(Restrictions.not(Restrictions.eq("gradename", "一年级"))).list(); 335 for(int i=0;i<grades.size();i++){ 336 System.out.println(grades.get(i)); 337 338 } 339 } catch (Exception e) { 340 // TODO: handle exception 341 e.printStackTrace(); 342 }finally{ 343 HibernateUtil.closeSession(); 344 345 } 346 347 } 348 /** 349 * 集合运算 350 */ 351 public void testCriterion6(){ 352 try { 353 session=HibernateUtil.currentSession(); 354 session.beginTransaction(); 355 List grades=session.createCriteria(Grade.class).add(Restrictions.isNotEmpty("stu")).list(); 356 for(int i=0;i<grades.size();i++){ 357 System.out.println(((Grade)grades.get(i)).getStu()); 358 } 359 360 361 } catch (Exception e) { 362 // TODO: handle exception 363 e.printStackTrace(); 364 }finally{ 365 HibernateUtil.closeSession(); 366 367 } 368 } 369 370 /** 371 * 动态查询 372 */ 373 public void testTrends(){ 374 try { 375 session=HibernateUtil.currentSession(); 376 session.beginTransaction(); 377 TrStudent tr=new TrStudent(); 378 tr.setName("%eli%"); 379 tr.setStartGrade(1); 380 tr.setEndGrade(3); 381 Criteria cri= session.createCriteria(Student.class); 382 if(tr.getName()!=null){ 383 cri.add(Restrictions.like("name", tr.getName())); 384 }if(tr.getStartGrade()!=null&&tr.getEndGrade()!=null){ 385 cri.add(Restrictions.between("gradeid",tr.getStartGrade(),tr.getEndGrade())); 386 387 }if(tr.getStartGrade()!=null&&tr.getEndGrade()==null){ 388 cri.add(Restrictions.ge("gradeid",tr.getStartGrade())); 389 390 } 391 if(tr.getStartGrade()==null&&tr.getEndGrade()!=null){ 392 cri.add(Restrictions.le("gradeid",tr.getEndGrade())); 393 394 } 395 List student=cri.addOrder(Order.asc("gradeid")).setMaxResults(80).list(); 396 //根据年级排序,每页显示十条 397 Integer pagesize=10; 398 Integer page=1; 399 System.out.println(student.size()/pagesize); 400 for(int i=0;i<student.size()/pagesize;i++){ 401 System.out.println("--------第 "+page+" 页-------------"); 402 List students=cri.addOrder(Order.asc("gradeid")).setFirstResult(pagesize*(page-1)).setMaxResults(pagesize).list(); 403 page++; 404 for(int j=0;j<students.size();j++){ 405 System.out.println(students.get(j)); 406 } 407 System.out.println(page); 408 409 410 411 } 412 413 414 } catch (Exception e) { 415 // TODO: handle exception 416 e.printStackTrace(); 417 }finally{ 418 HibernateUtil.closeSession(); 419 } 420 421 422 } 423 /** 424 * 链接查询 425 */ 426 public void testrelevance(){ 427 try { 428 session=HibernateUtil.currentSession(); 429 session.beginTransaction(); 430 List student=session.createCriteria(Student.class).createCriteria("grade").addOrder(Order.asc("gradeid")).setMaxResults(20).list(); 431 for(int i=0;i<student.size();i++){ 432 System.out.println(student.get(i)+"\t"+((Student)student.get(i)).getGrade().getGradename()); 433 } 434 435 436 437 } catch (Exception e) { 438 // TODO: handle exception 439 e.printStackTrace(); 440 }finally{ 441 HibernateUtil.closeSession(); 442 } 443 System.out.println("---createAlias()查询---"); 444 try { 445 session=HibernateUtil.currentSession(); 446 session.beginTransaction(); 447 List student=session.createCriteria(Student.class,"s").createAlias("grade","g").addOrder(Order.asc("s.gradeid")).setMaxResults(20).list(); 448 for(int i=0;i<student.size();i++){ 449 System.out.println(student.get(i)+"\t"+((Student)student.get(i)).getGrade().getGradename()); 450 } 451 452 } catch (Exception e) { 453 // TODO: handle exception 454 e.printStackTrace(); 455 }finally{ 456 HibernateUtil.closeSession(); 457 } 458 } 459 460 /** 461 * 投影查询 462 */ 463 public void testProj(){ 464 System.out.println("--查询记录总数--"); 465 try { 466 session=HibernateUtil.currentSession(); 467 session.beginTransaction(); 468 //查询所有年级名称 469 Object obj=session.createCriteria(Grade.class) 470 .setProjection(Projections.projectionList().add(Projections.rowCount())) 471 .list(); 472 System.out.println("所有班级:"+obj); 473 474 } catch (Exception e) { 475 // TODO: handle exception 476 e.printStackTrace(); 477 }finally{ 478 HibernateUtil.closeSession(); 479 } 480 481 System.out.println("--查询班级名称--"); 482 try { 483 session=HibernateUtil.currentSession(); 484 session.beginTransaction(); 485 //查询所有年级名称 486 Object obj=session.createCriteria(Grade.class) 487 .setProjection(Projections.projectionList().add(Property.forName("gradename"))) 488 .list(); 489 System.out.println(obj); 490 491 } catch (Exception e) { 492 // TODO: handle exception 493 e.printStackTrace(); 494 }finally{ 495 HibernateUtil.closeSession(); 496 } 497 } 498 499 /** 500 * DetachedCriteria 离线查询 501 */ 502 public void testoff_line(){ 503 try { 504 //这段代码一般放在web产生查询条件 505 DetachedCriteria det=DetachedCriteria.forClass(Student.class,"s") 506 .createAlias("s.grade", "g") 507 .add(Restrictions.eq("g.gradename", "幼儿园")); 508 509 //数据访问层 510 session=HibernateUtil.currentSession(); 511 session.beginTransaction(); 512 List students=det.getExecutableCriteria(session).add(Restrictions.ilike("s.name","%yap%")).setMaxResults(50).list(); 513 //打印 514 for(int i=0;i<students.size();i++){ 515 System.out.println(students.get(i)+"\t"+((Student)students.get(i)).getGrade().getGradename()); 516 } 517 518 } catch (Exception e) { 519 // TODO: handle exception 520 e.printStackTrace(); 521 }finally{ 522 HibernateUtil.closeSession(); 523 524 } 525 } 526 /**注解 的效果 527 * 启动时会在数据库创建一个表 528 */ 529 public void testNote(){ 530 try { 531 AnnotationConfiguration anc=new AnnotationConfiguration().configure(); 532 session=anc.buildSessionFactory().openSession(); 533 session.beginTransaction(); 534 session.getTransaction().commit(); 535 } catch (Exception e) { 536 // TODO: handle exception 537 e.printStackTrace(); 538 session.getTransaction().rollback(); 539 }finally{ 540 session.close(); 541 } 542 543 } 544 545 546 547 548 549 550 }
标签:des style blog http io ar color os 使用
原文地址:http://www.cnblogs.com/gcs1995/p/4160027.html