baomidou · Milkdove · Sep 3, 2024
diff --git a/...tis-plus-core/src/main/java/com/baomidou/mybatisplus/core/conditions/AbstractWrapper.java b/...tis-plus-core/src/main/java/com/baomidou/mybatisplus/core/conditions/AbstractWrapper.java
@@ -650,17 +650,17 @@ public String getParamAlias() {
     }
 
     /**
-     * 参数别名设置，初始化时优先设置该值、重复设置异常
+     * 参数别名设置，初始化时优先设置该值
      *
      * @param paramAlias 参数别名
      * @return Children
      */
-    @SuppressWarnings("unused")
     public Children setParamAlias(String paramAlias) {
-        Assert.notEmpty(paramAlias, "paramAlias can not be empty!");
-        Assert.isEmpty(paramNameValuePairs, "Please call this method before working!");
-        Assert.isNull(this.paramAlias, "Please do not call the method repeatedly!");
+        String oldParamAlias = getParamAlias();
         this.paramAlias = new SharedString(paramAlias);
+        if (this.expression != null && !oldParamAlias.equals(paramAlias)) {
+            expression.clearSqlSegmentCache();
+        }
         return typedThis;
     }
 

diff --git a/mybatis-plus-core/src/main/java/com/baomidou/mybatisplus/core/conditions/Wrapper.java b/mybatis-plus-core/src/main/java/com/baomidou/mybatisplus/core/conditions/Wrapper.java
@@ -70,7 +70,7 @@ public String getSqlFirst() {
      * 1. 逻辑删除需要自己拼接条件 (之前自定义也同样)
      * 2. 不支持wrapper中附带实体的情况 (wrapper自带实体会更麻烦)
      * 3. 用法 ${ew.customSqlSegment} (不需要where标签包裹,切记!)
-     * 4. ew是wrapper定义别名,不能使用其他的替换
+     * 4. ew是wrapper定义的默认别名,可通过{@link org.apache.ibatis.annotations.Param}注解修改，也可以通过{@link AbstractWrapper#setParamAlias(String)}方式设置别名
      */
     public String getCustomSqlSegment() {
         MergeSegments expression = getExpression();

diff --git a/...src/main/java/com/baomidou/mybatisplus/core/conditions/segments/AbstractISegmentList.java b/...src/main/java/com/baomidou/mybatisplus/core/conditions/segments/AbstractISegmentList.java
@@ -119,4 +119,9 @@ public void clear() {
         sqlSegment = EMPTY;
         cacheSqlSegment = true;
     }
+
+    public void clearSqlSegmentCache() {
+        sqlSegment = EMPTY;
+        cacheSqlSegment = false;
+    }
 }
diff --git a/...s-core/src/main/java/com/baomidou/mybatisplus/core/conditions/segments/MergeSegments.java b/...s-core/src/main/java/com/baomidou/mybatisplus/core/conditions/segments/MergeSegments.java
@@ -73,6 +73,15 @@ public String getSqlSegment() {
         return sqlSegment;
     }
 
+    public void clearSqlSegmentCache() {
+        sqlSegment = StringPool.EMPTY;
+        cacheSqlSegment = false;
+        normal.clearSqlSegmentCache();
+        groupBy.clearSqlSegmentCache();
+        having.clearSqlSegmentCache();
+        orderBy.clearSqlSegmentCache();
+    }
+
     /**
      * 清理
      *

diff --git a/...s-plus-core/src/main/java/com/baomidou/mybatisplus/core/override/MybatisMapperMethod.java b/...s-plus-core/src/main/java/com/baomidou/mybatisplus/core/override/MybatisMapperMethod.java
@@ -15,8 +15,12 @@
  */
 package com.baomidou.mybatisplus.core.override;
 
+import com.baomidou.mybatisplus.core.conditions.AbstractWrapper;
+import com.baomidou.mybatisplus.core.conditions.Wrapper;
 import com.baomidou.mybatisplus.core.metadata.IPage;
 import com.baomidou.mybatisplus.core.toolkit.Assert;
+
+import org.apache.ibatis.annotations.Param;
 import org.apache.ibatis.binding.BindingException;
 import org.apache.ibatis.binding.MapperMethod;
 import org.apache.ibatis.cursor.Cursor;
@@ -27,11 +31,15 @@
 import org.apache.ibatis.session.RowBounds;
 import org.apache.ibatis.session.SqlSession;
 
+import java.lang.annotation.Annotation;
 import java.lang.reflect.Array;
 import java.lang.reflect.Method;
+import java.util.Collections;
 import java.util.List;
 import java.util.Map;
 import java.util.Optional;
+import java.util.SortedMap;
+import java.util.TreeMap;
 
 /**
  * 从  {@link MapperMethod} copy 过来 </br>
@@ -45,27 +53,46 @@
 public class MybatisMapperMethod {
     private final MapperMethod.SqlCommand command;
     private final MapperMethod.MethodSignature method;
+    private final Map<Integer, String> wrapperParamsAliasNameMap;
 
     public MybatisMapperMethod(Class<?> mapperInterface, Method method, Configuration config) {
+        Annotation[][] paramAnnotations = method.getParameterAnnotations();
+        Class<?>[] parameterTypes = method.getParameterTypes();
+        int paramCount = method.getParameterCount();
+        final SortedMap<Integer, String> map = new TreeMap<>();
+        // get names from @Param annotations
+        for (int paramIndex = 0; paramIndex < paramCount; paramIndex++) {
+            String name = null;
+            for (Annotation annotation : paramAnnotations[paramIndex]) {
+                Class<?> parameterType = parameterTypes[paramIndex];
+                if (annotation instanceof Param && Wrapper.class.isAssignableFrom(parameterType)) {
+                    name = ((Param) annotation).value();
+                    break;
+                }
+            }
+            map.put(paramIndex, name);
+        }
+        wrapperParamsAliasNameMap = Collections.unmodifiableSortedMap(map);
         this.command = new MapperMethod.SqlCommand(config, mapperInterface, method);
         this.method = new MapperMethod.MethodSignature(config, mapperInterface, method);
     }
 
+
     public Object execute(SqlSession sqlSession, Object[] args) {
         Object result;
         switch (command.getType()) {
             case INSERT: {
-                Object param = method.convertArgsToSqlCommandParam(args);
+                Object param = this.convertArgsToSqlCommandParam(args);
                 result = rowCountResult(sqlSession.insert(command.getName(), param));
                 break;
             }
             case UPDATE: {
-                Object param = method.convertArgsToSqlCommandParam(args);
+                Object param = this.convertArgsToSqlCommandParam(args);
                 result = rowCountResult(sqlSession.update(command.getName(), param));
                 break;
             }
             case DELETE: {
-                Object param = method.convertArgsToSqlCommandParam(args);
+                Object param = this.convertArgsToSqlCommandParam(args);
                 result = rowCountResult(sqlSession.delete(command.getName(), param));
                 break;
             }
@@ -83,7 +110,7 @@ public Object execute(SqlSession sqlSession, Object[] args) {
                     if (IPage.class.isAssignableFrom(method.getReturnType())) {
                         result = executeForIPage(sqlSession, args);
                     } else {
-                        Object param = method.convertArgsToSqlCommandParam(args);
+                        Object param = this.convertArgsToSqlCommandParam(args);
                         result = sqlSession.selectOne(command.getName(), param);
                         if (method.returnsOptional()
                             && (result == null || !method.getReturnType().equals(result.getClass()))) {
@@ -115,7 +142,7 @@ private <E> Object executeForIPage(SqlSession sqlSession, Object[] args) {
             }
         }
         Assert.notNull(result, "can't found IPage for args!");
-        Object param = method.convertArgsToSqlCommandParam(args);
+        Object param = this.convertArgsToSqlCommandParam(args);
         List<E> list = sqlSession.selectList(command.getName(), param);
         result.setRecords(list);
         return result;
@@ -145,7 +172,7 @@ private void executeWithResultHandler(SqlSession sqlSession, Object[] args) {
                 + " needs either a @ResultMap annotation, a @ResultType annotation,"
                 + " or a resultType attribute in XML so a ResultHandler can be used as a parameter.");
         }
-        Object param = method.convertArgsToSqlCommandParam(args);
+        Object param = this.convertArgsToSqlCommandParam(args);
         if (method.hasRowBounds()) {
             RowBounds rowBounds = method.extractRowBounds(args);
             sqlSession.select(command.getName(), param, rowBounds, method.extractResultHandler(args));
@@ -156,7 +183,7 @@ private void executeWithResultHandler(SqlSession sqlSession, Object[] args) {
 
     private <E> Object executeForMany(SqlSession sqlSession, Object[] args) {
         List<E> result;
-        Object param = method.convertArgsToSqlCommandParam(args);
+        Object param = this.convertArgsToSqlCommandParam(args);
         if (method.hasRowBounds()) {
             RowBounds rowBounds = method.extractRowBounds(args);
             result = sqlSession.selectList(command.getName(), param, rowBounds);
@@ -176,7 +203,7 @@ private <E> Object executeForMany(SqlSession sqlSession, Object[] args) {
 
     private <T> Cursor<T> executeForCursor(SqlSession sqlSession, Object[] args) {
         Cursor<T> result;
-        Object param = method.convertArgsToSqlCommandParam(args);
+        Object param = this.convertArgsToSqlCommandParam(args);
         if (method.hasRowBounds()) {
             RowBounds rowBounds = method.extractRowBounds(args);
             result = sqlSession.selectCursor(command.getName(), param, rowBounds);
@@ -208,7 +235,7 @@ private <E> Object convertToArray(List<E> list) {
 
     private <K, V> Map<K, V> executeForMap(SqlSession sqlSession, Object[] args) {
         Map<K, V> result;
-        Object param = method.convertArgsToSqlCommandParam(args);
+        Object param = this.convertArgsToSqlCommandParam(args);
         if (method.hasRowBounds()) {
             RowBounds rowBounds = method.extractRowBounds(args);
             result = sqlSession.selectMap(command.getName(), param, method.getMapKey(), rowBounds);
@@ -217,4 +244,19 @@ private <K, V> Map<K, V> executeForMap(SqlSession sqlSession, Object[] args) {
         }
         return result;
     }
+
+    private Object convertArgsToSqlCommandParam(Object[] args) {
+        if (args == null) {
+            return null;
+        }
+        int argCount = args.length;
+        for (int i = 0; i < argCount; i++) {
+            Object arg = args[i];
+            String s = wrapperParamsAliasNameMap.get(i);
+            if (s != null && arg instanceof AbstractWrapper) {
+                ((AbstractWrapper<?, ?, ?>) arg).setParamAlias(s);
+            }
+        }
+        return method.convertArgsToSqlCommandParam(args);
+    }
 }
diff --git a/mybatis-plus/src/test/java/com/baomidou/mybatisplus/test/h2/H2UserTest.java b/mybatis-plus/src/test/java/com/baomidou/mybatisplus/test/h2/H2UserTest.java
@@ -487,6 +487,38 @@ void testSqlInjectionByCustomSqlSegment() {
         Assertions.assertEquals(2, h2Users.size());
     }
 
+
+    @Test
+    @Order(33)
+    void testWrapperSetAliasByParam() {
+        // Preparing: select * from h2user WHERE (name LIKE ?)
+        // Parameters: %y%%(String)
+        List<H2User> h2Users = userService.testWrapperSetAliasByParam(new QueryWrapper<H2User>().like("name", "y%"));
+        Assertions.assertEquals(2, h2Users.size());
+    }
+
+    @Test
+    @Order(34)
+    void testMultiWrapperQuery() {
+        // Preparing: select * from h2user a inner join h2user b on a.name=b.name WHERE (a.name LIKE ?) and (b.name = ?)
+        // Parameters: %y%%(String), Jerry(String)
+        QueryWrapper<H2User> leftTable = new QueryWrapper<H2User>() {
+            @Override
+            protected String columnToString(String column) {
+                return "a." + super.columnToString(column);
+            }
+        }.like("name", "y%");
+        System.out.println(leftTable.getCustomSqlSegment());
+        QueryWrapper<H2User> rightTable = new QueryWrapper<H2User>() {
+            @Override
+            protected String columnToString(String column) {
+                return "b." + super.columnToString(column);
+            }
+        }.eq("name", "Jerry");
+        List<H2User> h2Users = userService.testMultiWrapperQuery(leftTable, rightTable);
+        Assertions.assertEquals(1, h2Users.size());
+    }
+
     @Test
     void myQueryWithGroupByOrderBy() {
         userService.mySelectMaps().forEach(System.out::println);

diff --git a/mybatis-plus/src/test/java/com/baomidou/mybatisplus/test/h2/mapper/H2UserMapper.java b/mybatis-plus/src/test/java/com/baomidou/mybatisplus/test/h2/mapper/H2UserMapper.java
@@ -66,6 +66,12 @@ public interface H2UserMapper extends SuperMapper<H2User> {
     @Select("select * from h2user ${ew.customSqlSegment}")
     List<H2User> selectTestCustomSqlSegment(@Param(Constants.WRAPPER) Wrapper wrapper);
 
+    @Select("select * from h2user ${ewAlias.customSqlSegment}")
+    List<H2User> testWrapperSetAliasByParam(@Param("ewAlias") Wrapper wrapper);
+
+    @Select("select * from h2user a inner join h2user b on a.name=b.name ${asd.customSqlSegment} and ${haha.sqlSegment}")
+    List<H2User> testMultiWrapperQuery(@Param("haha") Wrapper haha, @Param("asd") Wrapper wrapper2);
+
     @Select("select count(1) from (" +
         "select test_id as id, CAST(#{nameParam} AS VARCHAR) as name" +
         " from h2user " +

diff --git a/mybatis-plus/src/test/java/com/baomidou/mybatisplus/test/h2/service/IH2UserService.java b/mybatis-plus/src/test/java/com/baomidou/mybatisplus/test/h2/service/IH2UserService.java
@@ -46,6 +46,10 @@ public interface IH2UserService extends IService<H2User> {
 
     List<H2User> testCustomSqlSegment(Wrapper wrapper);
 
+    List<H2User> testWrapperSetAliasByParam(Wrapper wrapper);
+
+    List<H2User> testMultiWrapperQuery(Wrapper wrapper, Wrapper wrapper2);
+
     void testSaveOrUpdateTransactional1(List<H2User> users);
 
     void testSaveOrUpdateTransactional2(List<H2User> users);

diff --git a/...s-plus/src/test/java/com/baomidou/mybatisplus/test/h2/service/impl/H2UserServiceImpl.java b/...s-plus/src/test/java/com/baomidou/mybatisplus/test/h2/service/impl/H2UserServiceImpl.java
@@ -128,6 +128,16 @@ public List<H2User> testCustomSqlSegment(Wrapper wrapper) {
         return baseMapper.selectTestCustomSqlSegment(wrapper);
     }
 
+    @Override
+    public List<H2User> testWrapperSetAliasByParam(Wrapper wrapper) {
+        return baseMapper.testWrapperSetAliasByParam(wrapper);
+    }
+
+    @Override
+    public List<H2User> testMultiWrapperQuery(Wrapper wrapper, Wrapper wrapper2) {
+        return baseMapper.testMultiWrapperQuery(wrapper, wrapper2);
+    }
+
     @Override
     @Transactional(rollbackFor = RuntimeException.class)
     public void testSaveOrUpdateTransactional1(List<H2User> users) {