From e90fa2b6bf2ad84e5c923e05fe8bcc7bff9b58dc Mon Sep 17 00:00:00 2001 From: CHENTIANMING002 Date: Mon, 9 Nov 2020 21:07:59 +0800 Subject: [PATCH] =?UTF-8?q?=E6=B8=90=E8=BF=9B=E5=BC=8F=E5=A4=84=E7=90=86Ma?= =?UTF-8?q?pper?= MIME-Version: 1.0 Content-Type: text/plain; charset=UTF-8 Content-Transfer-Encoding: 8bit --- .../common/progressive/ProgressiveMapper.java | 159 ++++++++++++++++++ 1 file changed, 159 insertions(+) create mode 100644 base/src/main/java/tk/mybatis/mapper/common/progressive/ProgressiveMapper.java diff --git a/base/src/main/java/tk/mybatis/mapper/common/progressive/ProgressiveMapper.java b/base/src/main/java/tk/mybatis/mapper/common/progressive/ProgressiveMapper.java new file mode 100644 index 000000000..6e311416e --- /dev/null +++ b/base/src/main/java/tk/mybatis/mapper/common/progressive/ProgressiveMapper.java @@ -0,0 +1,159 @@ +package tk.mybatis.mapper.common.progressive; + +import org.apache.ibatis.session.RowBounds; +import tk.mybatis.mapper.annotation.RegisterMapper; +import tk.mybatis.mapper.common.ExampleMapper; +import tk.mybatis.mapper.common.rowbounds.SelectByExampleRowBoundsMapper; +import tk.mybatis.mapper.entity.Example; +import tk.mybatis.mapper.util.Assert; +import tk.mybatis.mapper.util.Sqls; + +import java.lang.reflect.Field; +import java.lang.reflect.ParameterizedType; +import java.lang.reflect.Type; +import java.util.List; +import java.util.function.Consumer; + +/** + * 渐进式处理Mapper，数据库必须包含id字段 + * @author 陈添明 + */ +@RegisterMapper +public interface ProgressiveMapper extends ExampleMapper, SelectByExampleRowBoundsMapper { + + /** + * 渐进式记录处理 + * 数据表必须包含id字段 + * @param consumer 业务处理逻辑 + * @throws NoSuchFieldException 没有id字段会抛出此异常 + * @throws IllegalAccessException 无法访问id字段会抛出此异常 + */ + default void handleRecordProgressive(Consumer consumer) throws NoSuchFieldException, IllegalAccessException { + Class clz = getParameterType(); + long i = 0; + while (true) { + Example example = Example.builder(clz) + .andWhere(Sqls.custom().andGreaterThan("id", i)) + .build(); + List list = selectByExampleAndRowBounds(example, new RowBounds(0, 100)); + if (list.isEmpty()) { + return; + } + for (T t : list) { + consumer.accept(t); + } + T t = list.get(list.size() - 1); + + Field idField = t.getClass().getDeclaredField("id"); + idField.setAccessible(true); + i = (Long) idField.get(t); + } + + } + + /** + * 渐进式全量删除 + * 数据表必须包含id字段 + * 不会因为数据量大导致慢sql + * @throws NoSuchFieldException 没有id字段会抛出此异常 + * @throws IllegalAccessException 无法访问id字段会抛出此异常 + */ + default void deleteAllProgressive() throws NoSuchFieldException, IllegalAccessException { + Class parameterType = getParameterType(); + Long minimumId = getMinimumId(); + if (minimumId == null) { + return; + } + + Long maxId = getMaxId(); + if (maxId == null) { + return; + } + + for (Long i = minimumId; i <= maxId; ) { + i = i + 10000; + Example example = Example.builder(parameterType) + .andWhere(Sqls.custom().andBetween("id", minimumId, i)) + .build(); + deleteByExample(example); + } + } + + /** + * 获取泛型参数Class + * + * @return 泛型参数Class + */ + default Class getParameterType() { + Type[] genericInterfaces = this.getClass().getGenericInterfaces(); + Class rawClass = (Class) genericInterfaces[0]; + Type[] rawClassGenericInterfaces = rawClass.getGenericInterfaces(); + Assert.isTrue(rawClassGenericInterfaces.length > 0, "Mapper类必须继承泛型Mapper"); + ParameterizedType mapperType = getParameterizedType(rawClassGenericInterfaces); + Assert.notNull(mapperType, "未找到参数化Mapper类型！"); + return (Class) mapperType.getActualTypeArguments()[0]; + } + + /** + * 获取ParameterizedType + * @param rawClassGenericInterfaces 参数化接口 + * @return ParameterizedType + */ + default ParameterizedType getParameterizedType(Type[] rawClassGenericInterfaces) { + for (Type genericInterface : rawClassGenericInterfaces) { + if (genericInterface instanceof ParameterizedType) { + return (ParameterizedType) genericInterface; + } + } + return null; + } + + + /** + * 获取最小id + * @return 最小id + * @throws NoSuchFieldException 没有id字段会抛出此异常 + * @throws IllegalAccessException 无法访问id字段会抛出此异常 + */ + default Long getMinimumId() throws NoSuchFieldException, IllegalAccessException { + Class parameterType = getParameterType(); + Example example = Example.builder(parameterType) + .select("id") + .orderBy("id") + .build(); + + List list = selectByExampleAndRowBounds(example, new RowBounds(0, 1)); + if (list.isEmpty()) { + return null; + } + T t = list.get(0); + Field idField = t.getClass().getDeclaredField("id"); + idField.setAccessible(true); + return (Long) idField.get(t); + } + + /** + * 获取最大id + * @return 最大id + * @throws NoSuchFieldException 没有id字段会抛出此异常 + * @throws IllegalAccessException 无法访问id字段会抛出此异常 + */ + default Long getMaxId() throws NoSuchFieldException, IllegalAccessException { + Class parameterType = getParameterType(); + Example example = Example.builder(parameterType) + .select("id") + .orderByDesc("id") + .build(); + + List list = selectByExampleAndRowBounds(example, new RowBounds(0, 1)); + if (list.isEmpty()) { + return null; + } + T t = list.get(0); + Field idField = t.getClass().getDeclaredField("id"); + idField.setAccessible(true); + return (Long) idField.get(t); + } + + +}