什么是逆向工程：

mybaits需要程序员自己编写sql语句，mybatis官方提供逆向工程 可以针对单表自动生成mybatis执行所需要的代码（mapper.java,mapper.xml、po..）

1）下载逆向工程：

mybatis-generator-core-1.3.2-bundle.zip

2）使用java程序和xml配置生成代码：

其中GeneratorSqlmap.java:

1 import java.io.File; 2 import java.util.ArrayList; 3 import java.util.List; 4  5 import org.mybatis.generator.api.MyBatisGenerator; 6 import org.mybatis.generator.config.Configuration; 7 import org.mybatis.generator.config.xml.ConfigurationParser; 8 import org.mybatis.generator.internal.DefaultShellCallback; 9 10 public class GeneratorSqlmap {11 12     public void generator() throws Exception{13         List
      
        warnings = new ArrayList
       
        ();14         boolean overwrite = true;15         //指定 逆向工程配置文件16         File configFile = new File("generatorConfig.xml"); 17         ConfigurationParser cp = new ConfigurationParser(warnings);18         Configuration config = cp.parseConfiguration(configFile);19         DefaultShellCallback callback = new DefaultShellCallback(overwrite);20         MyBatisGenerator myBatisGenerator = new MyBatisGenerator(config,21                 callback, warnings);22         myBatisGenerator.generate(null);23     } 24     25     public static void main(String[] args) throws Exception {26         try {27             GeneratorSqlmap generatorSqlmap = new GeneratorSqlmap();28             generatorSqlmap.generator();29         } catch (Exception e) {30             e.printStackTrace();31         }32     }33 }
       
      

生成代码配置文件generatorConfig.xml：

1 
       2  5  6 
      
        7     
       
         8         
        
          9             
         10             
         11         
        12         
        13         
        
         16         
        17         
        22 23         
        25         
        
         26             
         27         
        28 29         
        30         
        
         32             
         33             
         34             
         35             
         36         
        37         
        38         
        
         40             
         41             
         42         
        43         
        44         
        
         47             
         48             
         49         
        50         
        51         
        52         
        53         
        54         
        55         
        60         61         
        65     
       66 
      

执行GeneratorSqlmap.java生成代码：

生成后代码：

3）使用生成的代码：

将生成工程中所生成的代码拷贝到自己的工程中。

举以下的例子：

将ItemsMapper.java/ItemsMapper.xml   Items.java/ItemsExample.java拷贝进项目中；使用这些mapper来做试验：

ItemsMapper.java接口：和ItemsMapper.xml:

1 package com.ssm.mapper; 2  3 import com.ssm.po.Items; 4 import com.ssm.po.ItemsExample; 5 import java.util.List; 6 import org.apache.ibatis.annotations.Param; 7  8 public interface ItemsMapper { 9     int countByExample(ItemsExample example);10 11     int deleteByExample(ItemsExample example);12 13     int deleteByPrimaryKey(Integer id);14 15     int insert(Items record);16 17     int insertSelective(Items record);18 19     List
      
        selectByExampleWithBLOBs(ItemsExample example);20 21     List
       
         selectByExample(ItemsExample example);22 23     Items selectByPrimaryKey(Integer id);24 25     int updateByExampleSelective(@Param("record") Items record, @Param("example") ItemsExample example);26 27     int updateByExampleWithBLOBs(@Param("record") Items record, @Param("example") ItemsExample example);28 29     int updateByExample(@Param("record") Items record, @Param("example") ItemsExample example);30 31     int updateByPrimaryKeySelective(Items record);32 33     int updateByPrimaryKeyWithBLOBs(Items record);34 35     int updateByPrimaryKey(Items record);36 }
       
      

1 
        2   3 
      
         4   
       
          5     
          6     
          7     
          8     
          9     
         10   
        11   
       
         12     
         13   
        14   
       
         15     
        
          16       
         
           17         
          
            18           
           
             19 
            
              20 
             
               21 
              
                22 and ${criterion.condition} 23 
               24 
              
                25 and ${criterion.condition} #{criterion.value} 26 
               27 
              
                28 and ${criterion.condition} #{criterion.value} and #{criterion.secondValue} 29 
               30 
              
                31 and ${criterion.condition} 32 
               
                 33 #{listItem} 34 
                35 
               36 
              37 
             38 
            39         
           40       
          41     
         42   
        43   
       
         44     
        
          45       
         
           46         
          
            47           
           
             48 
            
              49 
             
               50 
              
                51 and ${criterion.condition} 52 
               53 
              
                54 and ${criterion.condition} #{criterion.value} 55 
               56 
              
                57 and ${criterion.condition} #{criterion.value} and #{criterion.secondValue} 58 
               59 
              
                60 and ${criterion.condition} 61 
               
                 62 #{listItem} 63 
                64 
               65 
              66 
             67 
            68         
           69       
          70     
         71   
        72   
       
         73     id, name, price, pic, createtime 74   
        75   
       
         76     detail 77   
        78   
        79     select 80      81       distinct 82      83      84     , 85      86     from items 87      88        89      90      91       order by ${orderByClause} 92      93    94   
        95     select 96      97       distinct 98      99     100     from items101     102       103     104     105       order by ${orderByClause}106     107   108   
       109     select 110     111     ,112     113     from items114     where id = #{id,jdbcType=INTEGER}115   116   
       
        117     delete from items118     where id = #{id,jdbcType=INTEGER}119   
       120   
       
        121     delete from items122     
        
         123       
         124     
        125   
       126   
       
        127     insert into items (id, name, price, 128       pic, createtime, detail129       )130     values (#{id,jdbcType=INTEGER}, #{name,jdbcType=VARCHAR}, #{price,jdbcType=REAL}, 131       #{pic,jdbcType=VARCHAR}, #{createtime,jdbcType=TIMESTAMP}, #{detail,jdbcType=LONGVARCHAR}132       )133   
       134   
       
        135     insert into items136     
        
         137       
         
          138         id,139       
         140       
         
          141         name,142       
         143       
         
          144         price,145       
         146       
         
          147         pic,148       
         149       
         
          150         createtime,151       
         152       
         
          153         detail,154       
         155     
        156     
        
         157       
         
          158         #{id,jdbcType=INTEGER},159       
         160       
         
          161         #{name,jdbcType=VARCHAR},162       
         163       
         
          164         #{price,jdbcType=REAL},165       
         166       
         
          167         #{pic,jdbcType=VARCHAR},168       
         169       
         
          170         #{createtime,jdbcType=TIMESTAMP},171       
         172       
         
          173         #{detail,jdbcType=LONGVARCHAR},174       
         175     
        176   
       177   
       178     select count(*) from items179     180       181     182   183   
       
        184     update items185     
        
         186       
         
          187         id = #{record.id,jdbcType=INTEGER},188       
         189       
         
          190         name = #{record.name,jdbcType=VARCHAR},191       
         192       
         
          193         price = #{record.price,jdbcType=REAL},194       
         195       
         
          196         pic = #{record.pic,jdbcType=VARCHAR},197       
         198       
         
          199         createtime = #{record.createtime,jdbcType=TIMESTAMP},200       
         201       
         
          202         detail = #{record.detail,jdbcType=LONGVARCHAR},203       
         204     
        205     
        
         206       
         207     
        208   
       209   
       
        210     update items211     set id = #{record.id,jdbcType=INTEGER},212       name = #{record.name,jdbcType=VARCHAR},213       price = #{record.price,jdbcType=REAL},214       pic = #{record.pic,jdbcType=VARCHAR},215       createtime = #{record.createtime,jdbcType=TIMESTAMP},216       detail = #{record.detail,jdbcType=LONGVARCHAR}217     
        
         218       
         219     
        220   
       221   
       
        222     update items223     set id = #{record.id,jdbcType=INTEGER},224       name = #{record.name,jdbcType=VARCHAR},225       price = #{record.price,jdbcType=REAL},226       pic = #{record.pic,jdbcType=VARCHAR},227       createtime = #{record.createtime,jdbcType=TIMESTAMP}228     
        
         229       
         230     
        231   
       232   
       
        233     update items234     
        
         235       
         
          236         name = #{name,jdbcType=VARCHAR},237       
         238       
         
          239         price = #{price,jdbcType=REAL},240       
         241       
         
          242         pic = #{pic,jdbcType=VARCHAR},243       
         244       
         
          245         createtime = #{createtime,jdbcType=TIMESTAMP},246       
         247       
         
          248         detail = #{detail,jdbcType=LONGVARCHAR},249       
         250     
        251     where id = #{id,jdbcType=INTEGER}252   
       253   
       
        254     update items255     set name = #{name,jdbcType=VARCHAR},256       price = #{price,jdbcType=REAL},257       pic = #{pic,jdbcType=VARCHAR},258       createtime = #{createtime,jdbcType=TIMESTAMP},259       detail = #{detail,jdbcType=LONGVARCHAR}260     where id = #{id,jdbcType=INTEGER}261   
       262   
       
        263     update items264     set name = #{name,jdbcType=VARCHAR},265       price = #{price,jdbcType=REAL},266       pic = #{pic,jdbcType=VARCHAR},267       createtime = #{createtime,jdbcType=TIMESTAMP}268     where id = #{id,jdbcType=INTEGER}269   
       270 
      

Items.java 和 ItemsExample.java:

1 package com.ssm.po; 2  3 import java.util.Date; 4  5 public class Items { 6     private Integer id; 7  8     private String name; 9 10     private Float price;11 12     private String pic;13 14     private Date createtime;15 16     private String detail;17 18     public Integer getId() {19         return id;20     }21 22     public void setId(Integer id) {23         this.id = id;24     }25 26     public String getName() {27         return name;28     }29 30     public void setName(String name) {31         this.name = name == null ? null : name.trim();32     }33 34     public Float getPrice() {35         return price;36     }37 38     public void setPrice(Float price) {39         this.price = price;40     }41 42     public String getPic() {43         return pic;44     }45 46     public void setPic(String pic) {47         this.pic = pic == null ? null : pic.trim();48     }49 50     public Date getCreatetime() {51         return createtime;52     }53 54     public void setCreatetime(Date createtime) {55         this.createtime = createtime;56     }57 58     public String getDetail() {59         return detail;60     }61 62     public void setDetail(String detail) {63         this.detail = detail == null ? null : detail.trim();64     }65 }

1 package com.ssm.po;  2   3 import java.util.ArrayList;  4 import java.util.Date;  5 import java.util.List;  6   7 public class ItemsExample {  8     protected String orderByClause;  9  10     protected boolean distinct; 11  12     protected List
      
        oredCriteria; 13  14     public ItemsExample() { 15         oredCriteria = new ArrayList
       
        (); 16     } 17  18     public void setOrderByClause(String orderByClause) { 19         this.orderByClause = orderByClause; 20     } 21  22     public String getOrderByClause() { 23         return orderByClause; 24     } 25  26     public void setDistinct(boolean distinct) { 27         this.distinct = distinct; 28     } 29  30     public boolean isDistinct() { 31         return distinct; 32     } 33  34     public List
        
          getOredCriteria() { 35         return oredCriteria; 36     } 37  38     public void or(Criteria criteria) { 39         oredCriteria.add(criteria); 40     } 41  42     public Criteria or() { 43         Criteria criteria = createCriteriaInternal(); 44         oredCriteria.add(criteria); 45         return criteria; 46     } 47  48     public Criteria createCriteria() { 49         Criteria criteria = createCriteriaInternal(); 50         if (oredCriteria.size() == 0) { 51             oredCriteria.add(criteria); 52         } 53         return criteria; 54     } 55  56     protected Criteria createCriteriaInternal() { 57         Criteria criteria = new Criteria(); 58         return criteria; 59     } 60  61     public void clear() { 62         oredCriteria.clear(); 63         orderByClause = null; 64         distinct = false; 65     } 66  67     protected abstract static class GeneratedCriteria { 68         protected List
         
           criteria; 69  70         protected GeneratedCriteria() { 71             super(); 72             criteria = new ArrayList
          
           (); 73         } 74  75         public boolean isValid() { 76             return criteria.size() > 0; 77         } 78  79         public List
           
             getAllCriteria() { 80 return criteria; 81 } 82 83 public List
            
              getCriteria() { 84 return criteria; 85 } 86 87 protected void addCriterion(String condition) { 88 if (condition == null) { 89 throw new RuntimeException("Value for condition cannot be null"); 90 } 91 criteria.add(new Criterion(condition)); 92 } 93 94 protected void addCriterion(String condition, Object value, String property) { 95 if (value == null) { 96 throw new RuntimeException("Value for " + property + " cannot be null"); 97 } 98 criteria.add(new Criterion(condition, value)); 99 }100 101 protected void addCriterion(String condition, Object value1, Object value2, String property) {102 if (value1 == null || value2 == null) {103 throw new RuntimeException("Between values for " + property + " cannot be null");104 }105 criteria.add(new Criterion(condition, value1, value2));106 }107 108 public Criteria andIdIsNull() {109 addCriterion("id is null");110 return (Criteria) this;111 }112 113 public Criteria andIdIsNotNull() {114 addCriterion("id is not null");115 return (Criteria) this;116 }117 118 public Criteria andIdEqualTo(Integer value) {119 addCriterion("id =", value, "id");120 return (Criteria) this;121 }122 123 public Criteria andIdNotEqualTo(Integer value) {124 addCriterion("id <>", value, "id");125 return (Criteria) this;126 }127 128 public Criteria andIdGreaterThan(Integer value) {129 addCriterion("id >", value, "id");130 return (Criteria) this;131 }132 133 public Criteria andIdGreaterThanOrEqualTo(Integer value) {134 addCriterion("id >=", value, "id");135 return (Criteria) this;136 }137 138 public Criteria andIdLessThan(Integer value) {139 addCriterion("id <", value, "id");140 return (Criteria) this;141 }142 143 public Criteria andIdLessThanOrEqualTo(Integer value) {144 addCriterion("id <=", value, "id");145 return (Criteria) this;146 }147 148 public Criteria andIdIn(List
             
               values) {149 addCriterion("id in", values, "id");150 return (Criteria) this;151 }152 153 public Criteria andIdNotIn(List
              
                values) {154 addCriterion("id not in", values, "id");155 return (Criteria) this;156 }157 158 public Criteria andIdBetween(Integer value1, Integer value2) {159 addCriterion("id between", value1, value2, "id");160 return (Criteria) this;161 }162 163 public Criteria andIdNotBetween(Integer value1, Integer value2) {164 addCriterion("id not between", value1, value2, "id");165 return (Criteria) this;166 }167 168 public Criteria andNameIsNull() {169 addCriterion("name is null");170 return (Criteria) this;171 }172 173 public Criteria andNameIsNotNull() {174 addCriterion("name is not null");175 return (Criteria) this;176 }177 178 public Criteria andNameEqualTo(String value) {179 addCriterion("name =", value, "name");180 return (Criteria) this;181 }182 183 public Criteria andNameNotEqualTo(String value) {184 addCriterion("name <>", value, "name");185 return (Criteria) this;186 }187 188 public Criteria andNameGreaterThan(String value) {189 addCriterion("name >", value, "name");190 return (Criteria) this;191 }192 193 public Criteria andNameGreaterThanOrEqualTo(String value) {194 addCriterion("name >=", value, "name");195 return (Criteria) this;196 }197 198 public Criteria andNameLessThan(String value) {199 addCriterion("name <", value, "name");200 return (Criteria) this;201 }202 203 public Criteria andNameLessThanOrEqualTo(String value) {204 addCriterion("name <=", value, "name");205 return (Criteria) this;206 }207 208 public Criteria andNameLike(String value) {209 addCriterion("name like", value, "name");210 return (Criteria) this;211 }212 213 public Criteria andNameNotLike(String value) {214 addCriterion("name not like", value, "name");215 return (Criteria) this;216 }217 218 public Criteria andNameIn(List
               
                 values) {219 addCriterion("name in", values, "name");220 return (Criteria) this;221 }222 223 public Criteria andNameNotIn(List
                
                  values) {224 addCriterion("name not in", values, "name");225 return (Criteria) this;226 }227 228 public Criteria andNameBetween(String value1, String value2) {229 addCriterion("name between", value1, value2, "name");230 return (Criteria) this;231 }232 233 public Criteria andNameNotBetween(String value1, String value2) {234 addCriterion("name not between", value1, value2, "name");235 return (Criteria) this;236 }237 238 public Criteria andPriceIsNull() {239 addCriterion("price is null");240 return (Criteria) this;241 }242 243 public Criteria andPriceIsNotNull() {244 addCriterion("price is not null");245 return (Criteria) this;246 }247 248 public Criteria andPriceEqualTo(Float value) {249 addCriterion("price =", value, "price");250 return (Criteria) this;251 }252 253 public Criteria andPriceNotEqualTo(Float value) {254 addCriterion("price <>", value, "price");255 return (Criteria) this;256 }257 258 public Criteria andPriceGreaterThan(Float value) {259 addCriterion("price >", value, "price");260 return (Criteria) this;261 }262 263 public Criteria andPriceGreaterThanOrEqualTo(Float value) {264 addCriterion("price >=", value, "price");265 return (Criteria) this;266 }267 268 public Criteria andPriceLessThan(Float value) {269 addCriterion("price <", value, "price");270 return (Criteria) this;271 }272 273 public Criteria andPriceLessThanOrEqualTo(Float value) {274 addCriterion("price <=", value, "price");275 return (Criteria) this;276 }277 278 public Criteria andPriceIn(List
                 
                   values) {279 addCriterion("price in", values, "price");280 return (Criteria) this;281 }282 283 public Criteria andPriceNotIn(List
                  
                    values) {284 addCriterion("price not in", values, "price");285 return (Criteria) this;286 }287 288 public Criteria andPriceBetween(Float value1, Float value2) {289 addCriterion("price between", value1, value2, "price");290 return (Criteria) this;291 }292 293 public Criteria andPriceNotBetween(Float value1, Float value2) {294 addCriterion("price not between", value1, value2, "price");295 return (Criteria) this;296 }297 298 public Criteria andPicIsNull() {299 addCriterion("pic is null");300 return (Criteria) this;301 }302 303 public Criteria andPicIsNotNull() {304 addCriterion("pic is not null");305 return (Criteria) this;306 }307 308 public Criteria andPicEqualTo(String value) {309 addCriterion("pic =", value, "pic");310 return (Criteria) this;311 }312 313 public Criteria andPicNotEqualTo(String value) {314 addCriterion("pic <>", value, "pic");315 return (Criteria) this;316 }317 318 public Criteria andPicGreaterThan(String value) {319 addCriterion("pic >", value, "pic");320 return (Criteria) this;321 }322 323 public Criteria andPicGreaterThanOrEqualTo(String value) {324 addCriterion("pic >=", value, "pic");325 return (Criteria) this;326 }327 328 public Criteria andPicLessThan(String value) {329 addCriterion("pic <", value, "pic");330 return (Criteria) this;331 }332 333 public Criteria andPicLessThanOrEqualTo(String value) {334 addCriterion("pic <=", value, "pic");335 return (Criteria) this;336 }337 338 public Criteria andPicLike(String value) {339 addCriterion("pic like", value, "pic");340 return (Criteria) this;341 }342 343 public Criteria andPicNotLike(String value) {344 addCriterion("pic not like", value, "pic");345 return (Criteria) this;346 }347 348 public Criteria andPicIn(List
                   
                     values) {349 addCriterion("pic in", values, "pic");350 return (Criteria) this;351 }352 353 public Criteria andPicNotIn(List
                    
                      values) {354 addCriterion("pic not in", values, "pic");355 return (Criteria) this;356 }357 358 public Criteria andPicBetween(String value1, String value2) {359 addCriterion("pic between", value1, value2, "pic");360 return (Criteria) this;361 }362 363 public Criteria andPicNotBetween(String value1, String value2) {364 addCriterion("pic not between", value1, value2, "pic");365 return (Criteria) this;366 }367 368 public Criteria andCreatetimeIsNull() {369 addCriterion("createtime is null");370 return (Criteria) this;371 }372 373 public Criteria andCreatetimeIsNotNull() {374 addCriterion("createtime is not null");375 return (Criteria) this;376 }377 378 public Criteria andCreatetimeEqualTo(Date value) {379 addCriterion("createtime =", value, "createtime");380 return (Criteria) this;381 }382 383 public Criteria andCreatetimeNotEqualTo(Date value) {384 addCriterion("createtime <>", value, "createtime");385 return (Criteria) this;386 }387 388 public Criteria andCreatetimeGreaterThan(Date value) {389 addCriterion("createtime >", value, "createtime");390 return (Criteria) this;391 }392 393 public Criteria andCreatetimeGreaterThanOrEqualTo(Date value) {394 addCriterion("createtime >=", value, "createtime");395 return (Criteria) this;396 }397 398 public Criteria andCreatetimeLessThan(Date value) {399 addCriterion("createtime <", value, "createtime");400 return (Criteria) this;401 }402 403 public Criteria andCreatetimeLessThanOrEqualTo(Date value) {404 addCriterion("createtime <=", value, "createtime");405 return (Criteria) this;406 }407 408 public Criteria andCreatetimeIn(List
                     
                       values) {409 addCriterion("createtime in", values, "createtime");410 return (Criteria) this;411 }412 413 public Criteria andCreatetimeNotIn(List
                      
                        values) {414 addCriterion("createtime not in", values, "createtime");415 return (Criteria) this;416 }417 418 public Criteria andCreatetimeBetween(Date value1, Date value2) {419 addCriterion("createtime between", value1, value2, "createtime");420 return (Criteria) this;421 }422 423 public Criteria andCreatetimeNotBetween(Date value1, Date value2) {424 addCriterion("createtime not between", value1, value2, "createtime");425 return (Criteria) this;426 }427 }428 429 public static class Criteria extends GeneratedCriteria {430 431 protected Criteria() {432 super();433 }434 }435 436 public static class Criterion {437 private String condition;438 439 private Object value;440 441 private Object secondValue;442 443 private boolean noValue;444 445 private boolean singleValue;446 447 private boolean betweenValue;448 449 private boolean listValue;450 451 private String typeHandler;452 453 public String getCondition() {454 return condition;455 }456 457 public Object getValue() {458 return value;459 }460 461 public Object getSecondValue() {462 return secondValue;463 }464 465 public boolean isNoValue() {466 return noValue;467 }468 469 public boolean isSingleValue() {470 return singleValue;471 }472 473 public boolean isBetweenValue() {474 return betweenValue;475 }476 477 public boolean isListValue() {478 return listValue;479 }480 481 public String getTypeHandler() {482 return typeHandler;483 }484 485 protected Criterion(String condition) {486 super();487 this.condition = condition;488 this.typeHandler = null;489 this.noValue = true;490 }491 492 protected Criterion(String condition, Object value, String typeHandler) {493 super();494 this.condition = condition;495 this.value = value;496 this.typeHandler = typeHandler;497 if (value instanceof List
                       ) {498 this.listValue = true;499 } else {500 this.singleValue = true;501 }502 }503 504 protected Criterion(String condition, Object value) {505 this(condition, value, null);506 }507 508 protected Criterion(String condition, Object value, Object secondValue, String typeHandler) {509 super();510 this.condition = condition;511 this.value = value;512 this.secondValue = secondValue;513 this.typeHandler = typeHandler;514 this.betweenValue = true;515 }516 517 protected Criterion(String condition, Object value, Object secondValue) {518 this(condition, value, secondValue, null);519 }520 }521 }
                      
                     
                    
                   
                  
                 
                
               
              
             
            
           
          
         
        
       
      

4）测试ItemsMapper中的方法：

1 package com.ssm.mapper; 2  3 import static org.junit.Assert.*; 4 import java.util.Date; 5 import java.util.List; 6 import org.junit.Before; 7 import org.junit.Test; 8 import org.springframework.context.ApplicationContext; 9 import org.springframework.context.support.ClassPathXmlApplicationContext;10 import com.ssm.po.Items;11 import com.ssm.po.ItemsExample;12 13 public class ItemsMapperTest {14     15     private ApplicationContext applicationContext;16     private ItemsMapper itemsMapper;17 18     @Before19     public void setUp() throws Exception {20         applicationContext = new ClassPathXmlApplicationContext("classpath:spring/applicationContext.xml");21         itemsMapper = (ItemsMapper) applicationContext.getBean("itemsMapper");22     }23     24     //根据主键删除 25     @Test26     public void testDeleteByPrimaryKey() {27         fail("Not yet implemented");28     }29     30     //插入31     @Test32     public void testInsert() {33         //构造 items对象34         Items items = new Items();35         items.setName("手机");36         items.setPrice(999f);37         items.setCreatetime(new Date());38         itemsMapper.insert(items);39     }40     41     //自定义条件查询42     @Test43     public void testSelectByExample() {44         ItemsExample itemsExample = new ItemsExample();45         //通过criteria构造查询条件46         ItemsExample.Criteria criteria = itemsExample.createCriteria();47         criteria.andNameEqualTo("手机");48         //可能返回多条记录49         List
      
        list = itemsMapper.selectByExample(itemsExample);50         System.out.println(list);51     }52     53     //根据主键查询54     @Test55     public void testSelectByPrimaryKey() {56         Items items = itemsMapper.selectByPrimaryKey(1);57         System.out.println(items);58     }59     60     //更新数据61     @Test62     public void testUpdateByPrimaryKey() {63         //对所有字段进行更新，需要先查询出来再更新64         Items items = itemsMapper.selectByPrimaryKey(4);65         items.setName("水杯");66         itemsMapper.updateByPrimaryKey(items);67         68         //如果传入字段不空为才更新，在批量更新中使用此方法，不需要先查询再更新69         //itemsMapper.updateByPrimaryKeySelective(record);70     }71 }
      

 

主要是看下逆向工程生成的mapper接口、mapper.xml配置文件；