add

qiaoba-commons/qiaoba-common-base/src/main/java/com/qiaoba/common/base/utils/AnnotationUtil.java

@@ -0,0 +1,33 @@
+package com.qiaoba.common.base.utils;
+
+import cn.hutool.core.util.ClassUtil;
+
+import java.lang.annotation.Annotation;
+import java.lang.reflect.Method;
+
+/**
+ * 注解Util
+ *
+ * @author ailanyin
+ * @version 1.0
+ * @since 2023/6/21 9:53
+ */
+public class AnnotationUtil extends cn.hutool.core.annotation.AnnotationUtil {
+
+    public static boolean hasAnnotation(String referenceMethod, Class<? extends Annotation> annotation) {
+        // com.qiaoba.common.base.utils.AnnotationUtil.hasAnnotation
+        StringBuilder sb = new StringBuilder(referenceMethod);
+        int index = sb.lastIndexOf(".");
+        // com.qiaoba.common.base.utils.AnnotationUtil
+        String clazzName = sb.substring(0, index);
+        // hasAnnotation
+        String methodName = sb.substring(index + 1, sb.length());
+        Class<?> clazz = ClassUtil.loadClass(clazzName);
+        for (Method method : clazz.getDeclaredMethods()) {
+            if (methodName.equals(method.getName())) {
+                return hasAnnotation(method, annotation);
+            }
+        }
+        return false;
+    }
+}

qiaoba-commons/qiaoba-common-datasource/src/main/java/com/qiaoba/common/database/annotations/SelectOneRow.java

@@ -0,0 +1,16 @@
+package com.qiaoba.common.database.annotations;
+
+import java.lang.annotation.*;
+
+/**
+ * 只查询一条数据
+ *
+ * @author ailanyin
+ * @version 1.0
+ * @since 2023/6/21 10:10
+ */
+@Target(ElementType.METHOD)
+@Retention(RetentionPolicy.RUNTIME)
+@Documented
+public @interface SelectOneRow {
+}

qiaoba-commons/qiaoba-common-datasource/src/main/java/com/qiaoba/common/database/config/MybatisPlusConfig.java

@@ -7,6 +7,7 @@ import com.baomidou.mybatisplus.extension.plugins.inner.PaginationInnerIntercept
 import com.baomidou.mybatisplus.extension.plugins.inner.TenantLineInnerInterceptor;
 import com.qiaoba.common.base.context.BaseContext;
 import com.qiaoba.common.database.interceptors.SchemaInterceptor;
+import com.qiaoba.common.database.interceptors.SelectOneRowInterceptor;
 import net.sf.jsqlparser.expression.Expression;
 import net.sf.jsqlparser.expression.StringValue;
 import org.springframework.context.annotation.Bean;
@@ -45,6 +46,7 @@ public class MybatisPlusConfig {
                 return IGNORE_TABLES.contains(tableName);
             }
         }));
+        interceptor.addInnerInterceptor(new SelectOneRowInterceptor());
         interceptor.addInnerInterceptor(new PaginationInnerInterceptor());
         return interceptor;
     }

qiaoba-commons/qiaoba-common-datasource/src/main/java/com/qiaoba/common/database/entity/PageQuery.java

@@ -47,12 +47,4 @@ public class PageQuery implements Serializable {
         return new Page<>(pageNum, pageSize);
     }
 
-    /**
-     * 只查第一条数据
-     *
-     * @return page
-     */
-    public static Page limit1() {
-        return new Page<>(1, 1);
-    }
 }

qiaoba-commons/qiaoba-common-datasource/src/main/java/com/qiaoba/common/database/interceptors/SelectOneRowInterceptor.java

@@ -0,0 +1,53 @@
+package com.qiaoba.common.database.interceptors;
+
+import com.baomidou.mybatisplus.core.toolkit.PluginUtils;
+import com.baomidou.mybatisplus.extension.plugins.inner.InnerInterceptor;
+import com.baomidou.mybatisplus.extension.plugins.pagination.DialectFactory;
+import com.baomidou.mybatisplus.extension.plugins.pagination.DialectModel;
+import com.baomidou.mybatisplus.extension.plugins.pagination.dialects.IDialect;
+import com.baomidou.mybatisplus.extension.toolkit.JdbcUtils;
+import com.qiaoba.common.base.utils.AnnotationUtil;
+import com.qiaoba.common.database.annotations.SelectOneRow;
+import org.apache.ibatis.executor.Executor;
+import org.apache.ibatis.mapping.BoundSql;
+import org.apache.ibatis.mapping.MappedStatement;
+import org.apache.ibatis.mapping.ParameterMapping;
+import org.apache.ibatis.session.Configuration;
+import org.apache.ibatis.session.ResultHandler;
+import org.apache.ibatis.session.RowBounds;
+
+import java.sql.SQLException;
+import java.util.List;
+import java.util.Map;
+
+/**
+ * 查询一条
+ * 因为Oracle 不支持 limit 1 写法, 故调用MP的分页方言处理
+ *
+ * @author ailanyin
+ * @version 1.0
+ * @since 2023/6/21 8:53
+ */
+public class SelectOneRowInterceptor implements InnerInterceptor {
+
+    @Override
+    public void beforeQuery(Executor executor, MappedStatement ms, Object parameter, RowBounds rowBounds, ResultHandler resultHandler, BoundSql boundSql) throws SQLException {
+        if (AnnotationUtil.hasAnnotation(ms.getId(), SelectOneRow.class)) {
+            String buildSql = boundSql.getSql();
+            IDialect dialect = DialectFactory.getDialect(JdbcUtils.getDbType(executor));
+            DialectModel model = dialect.buildPaginationSql(buildSql, 0, 1);
+            replaceSql(ms, boundSql, model);
+        }
+    }
+
+    private void replaceSql(MappedStatement ms, BoundSql boundSql, DialectModel model) {
+        PluginUtils.MPBoundSql mpBoundSql = PluginUtils.mpBoundSql(boundSql);
+        final Configuration configuration = ms.getConfiguration();
+        List<ParameterMapping> mappings = mpBoundSql.parameterMappings();
+        Map<String, Object> additionalParameter = mpBoundSql.additionalParameters();
+        model.consumers(mappings, configuration, additionalParameter);
+        mpBoundSql.sql(model.getDialectSql());
+        mpBoundSql.parameterMappings(mappings);
+    }
+
+}