add join as（lambdaGetter）support

docs/zh/base/query.md

@@ -80,6 +80,38 @@ List<ArticleDTO> results = mapper.selectListByQueryAs(query, ArticleDTO.class);
 System.out.println(results);
 ```
 
+假设 `ArticleDTO` 定义的属性和 SQL 查询的字段不一致时，例如：
+
+```java
+public class ArticleDTO {
+
+  private Long id;
+  private Long accountId;
+  private String title;
+  private String content;
+
+  //以下用户字段 和 用户表定义的列不一致，表定义的列为 user_name
+  private String authorName;
+  private int authorAge;
+  private Date birthday;
+}
+```
+
+那么， `QueryWrapper` 需要添加 as，修改如下：
+
+```java 3,4
+QueryWrapper asWrapper = QueryWrapper.create()
+    .select(ARTICLE.ALL_COLUMNS)
+    .select(ACCOUNT.USER_NAME.as(ArticleDTO::getAuthorName)
+            ,ACCOUNT.AGE.as(ArticleDTO::getAuthorAge)
+            ,ACCOUNT.BIRTHDAY
+    )
+    .from(ARTICLE)
+    .leftJoin(ACCOUNT).on(ARTICLE.ACCOUNT_ID.eq(ACCOUNT.ID))
+    .where(ACCOUNT.ID.ge(0));
+```
+
+
 **注意事项：**
 
 关联查询（`selectOneByQueryAs`、`selectListByQueryAs` 、`paginateAs` 等方法）中的 `asType` 参数类型（比如：`ArticleDTO`），

mybatis-flex-core/src/main/java/com/mybatisflex/core/query/QueryColumn.java

@@ -18,6 +18,8 @@ package com.mybatisflex.core.query;
 
 import com.mybatisflex.core.dialect.IDialect;
 import com.mybatisflex.core.table.TableDef;
+import com.mybatisflex.core.util.LambdaGetter;
+import com.mybatisflex.core.util.LambdaUtil;
 import com.mybatisflex.core.util.SqlUtil;
 import com.mybatisflex.core.util.StringUtil;
 
@@ -80,6 +82,10 @@ public class QueryColumn implements Serializable {
         this.alias = alias;
     }
 
+    public <T> QueryColumn as(LambdaGetter<T> fn) {
+        return as(LambdaUtil.getFieldName(fn));
+    }
+
     public QueryColumn as(String alias) {
         SqlUtil.keepColumnSafely(alias);
         QueryColumn newColumn = new QueryColumn();

mybatis-flex-core/src/main/java/com/mybatisflex/core/table/TableInfo.java

@@ -640,6 +640,16 @@ public class TableInfo {
                     .typeHandler(columnInfo.buildTypeHandler())
                     .build();
             resultMappings.add(mapping);
+
+            //add property mapper for sql as ...
+            if (!Objects.equals(columnInfo.getColumn(), columnInfo.getProperty())) {
+                ResultMapping propertyMapping = new ResultMapping.Builder(configuration, columnInfo.getProperty(),
+                        columnInfo.getProperty(), columnInfo.getPropertyType())
+                        .jdbcType(columnInfo.getJdbcType())
+                        .typeHandler(columnInfo.buildTypeHandler())
+                        .build();
+                resultMappings.add(propertyMapping);
+            }
         }
 
         for (IdInfo idInfo : primaryKeyList) {

mybatis-flex-core/src/main/java/com/mybatisflex/core/util/LambdaGetter.java

@@ -0,0 +1,24 @@
+/**
+ * Copyright (c) 2022-2023, Mybatis-Flex (fuhai999@gmail.com).
+ * <p>
+ * 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
+ * <p>
+ * http://www.apache.org/licenses/LICENSE-2.0
+ * <p>
+ * 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.mybatisflex.core.util;
+
+import java.io.Serializable;
+
+@FunctionalInterface
+public interface LambdaGetter<T> extends Serializable {
+    Object get(T source);
+}
+

mybatis-flex-core/src/main/java/com/mybatisflex/core/util/LambdaUtil.java

@@ -0,0 +1,50 @@
+/**
+ * Copyright (c) 2022-2023, Mybatis-Flex (fuhai999@gmail.com).
+ * <p>
+ * 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
+ * <p>
+ * http://www.apache.org/licenses/LICENSE-2.0
+ * <p>
+ * 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.mybatisflex.core.util;
+
+import org.apache.ibatis.reflection.property.PropertyNamer;
+import org.apache.ibatis.util.MapUtil;
+
+import java.io.Serializable;
+import java.lang.invoke.SerializedLambda;
+import java.lang.reflect.Method;
+import java.util.Map;
+import java.util.concurrent.ConcurrentHashMap;
+
+public class LambdaUtil {
+
+    private static final Map<Class<?>, SerializedLambda> lambdaMap = new ConcurrentHashMap<>();
+
+    public static <T> String getFieldName(LambdaGetter<T> getter) {
+        SerializedLambda lambda = getSerializedLambda(getter);
+        String methodName = lambda.getImplMethodName();
+        return PropertyNamer.methodToProperty(methodName);
+    }
+
+
+    private static SerializedLambda getSerializedLambda(Serializable getter) {
+        return MapUtil.computeIfAbsent(lambdaMap, getter.getClass(), aClass -> {
+            try {
+                Method method = getter.getClass().getDeclaredMethod("writeReplace");
+                method.setAccessible(Boolean.TRUE);
+                return (SerializedLambda) method.invoke(getter);
+            } catch (Exception e) {
+                throw new RuntimeException(e);
+            }
+        });
+    }
+
+}

mybatis-flex-test/mybatis-flex-native-test/src/main/java/com/mybatisflex/test/ArticleDTO.java

@@ -12,9 +12,9 @@ public class ArticleDTO {
 
     private String content;
 
-    private String userName;
+    private String authorName;
 
-    private int age;
+    private int authorAge;
 
     private Date birthday;
 
@@ -50,20 +50,21 @@ public class ArticleDTO {
         this.content = content;
     }
 
-    public String getUserName() {
-        return userName;
+
+    public String getAuthorName() {
+        return authorName;
     }
 
-    public void setUserName(String userName) {
-        this.userName = userName;
+    public void setAuthorName(String authorName) {
+        this.authorName = authorName;
     }
 
-    public int getAge() {
-        return age;
+    public int getAuthorAge() {
+        return authorAge;
     }
 
-    public void setAge(int age) {
-        this.age = age;
+    public void setAuthorAge(int authorAge) {
+        this.authorAge = authorAge;
     }
 
     public Date getBirthday() {
@@ -81,8 +82,8 @@ public class ArticleDTO {
                 ", accountId=" + accountId +
                 ", title='" + title + '\'' +
                 ", content='" + content + '\'' +
-                ", userName='" + userName + '\'' +
-                ", age=" + age +
+                ", authorName='" + authorName + '\'' +
+                ", authorAge=" + authorAge +
                 ", birthday=" + birthday +
                 '}';
     }

mybatis-flex-test/mybatis-flex-native-test/src/main/java/com/mybatisflex/test/EntityTestStarter.java

@@ -85,7 +85,10 @@ public class EntityTestStarter {
 //
         QueryWrapper asWrapper = QueryWrapper.create()
                 .select(ARTICLE.ALL_COLUMNS)
-                .select(ACCOUNT.USER_NAME,ACCOUNT.AGE,ACCOUNT.BIRTHDAY)
+                .select(ACCOUNT.USER_NAME.as(ArticleDTO::getAuthorName)
+                        ,ACCOUNT.AGE.as(ArticleDTO::getAuthorAge)
+                        ,ACCOUNT.BIRTHDAY
+                )
                 .from(ARTICLE)
                 .leftJoin(ACCOUNT).on(ARTICLE.ACCOUNT_ID.eq(ACCOUNT.ID))
                 .where(ACCOUNT.ID.ge(0));