修复 entityClass 为空时出现的NPE问题：从 lambda 表达式中推测实体类

mybatis-plus-core/src/main/java/com/baomidou/mybatisplus/core/conditions/AbstractLambdaWrapper.java

@@ -15,6 +15,8 @@
  */
 package com.baomidou.mybatisplus.core.conditions;
 
+import com.baomidou.mybatisplus.core.exceptions.MybatisPlusException;
+import com.baomidou.mybatisplus.core.toolkit.ExceptionUtils;
 import com.baomidou.mybatisplus.core.toolkit.LambdaUtils;
 import com.baomidou.mybatisplus.core.toolkit.StringPool;
 import com.baomidou.mybatisplus.core.toolkit.StringUtils;
@@ -63,11 +65,26 @@ public abstract class AbstractLambdaWrapper<T, Children extends AbstractLambdaWr
         return getColumn(LambdaUtils.resolve(column), onlyColumn);
     }
 
-    private String getColumn(SerializedLambda lambda, boolean onlyColumn) {
+    /**
+     * 获取 SerializedLambda 对应的列信息，从 lambda 表达式中推测实体类
+     * <p>
+     * 如果获取不到列信息，那么本次条件组装将会失败
+     *
+     * @param lambda     lambda 表达式
+     * @param onlyColumn 如果是，结果: "name", 如果否： "name" as "name"
+     * @return 列
+     * @throws com.baomidou.mybatisplus.core.exceptions.MybatisPlusException 获取不到列信息时抛出异常
+     * @see SerializedLambda#getImplClass()
+     * @see SerializedLambda#getImplMethodName()
+     */
+    private String getColumn(SerializedLambda lambda, boolean onlyColumn) throws MybatisPlusException {
         String fieldName = StringUtils.resolveFieldName(lambda.getImplMethodName());
-        return Optional.ofNullable(LambdaUtils.getColumnOfProperty(entityClass, fieldName))
+
+        return Optional.ofNullable(LambdaUtils.getColumnOfProperty(lambda.getImplClass(), fieldName))
             .map(onlyColumn ? ColumnCache::getColumn : ColumnCache::getColumnSelect)
-            .orElse(null);
+            .orElseThrow(() ->
+                ExceptionUtils.mpe("Your property named \"%s\" cannot find the corresponding database column name!", fieldName)
+            );
     }
 
 }

mybatis-plus/src/test/java/com/baomidou/mybatisplus/test/h2/H2UserTest.java

@@ -298,11 +298,13 @@ class H2UserTest extends BaseTest {
         H2User tomcat = userService.lambdaQuery().eq(H2User::getName, "Tomcat").one();
         Assertions.assertNotNull(tomcat);
         Assertions.assertNotEquals(0L, userService.lambdaQuery().like(H2User::getName, "a").count().longValue());
-        userService.lambdaQuery().like(H2User::getName, "T")
+
+        List<H2User> users = userService.lambdaQuery().like(H2User::getName, "T")
             .ne(H2User::getAge, AgeEnum.TWO)
             .ge(H2User::getVersion, 1)
             .isNull(H2User::getPrice)
             .list();
+        Assertions.assertTrue(users.isEmpty());
     }
 
     @Test