refactor rewrite (570cc1d7) · Commits · SUMMER2020 / students / proj-2004142

sharding-jdbc-core/src/main/java/io/shardingjdbc/core/rewrite/SQLBuilder.java

+30 −61

Original line number	Diff line number	Diff line
		@@ -20,9 +20,12 @@ package io.shardingjdbc.core.rewrite;
		import com.google.common.base.Optional;
		import com.google.common.base.Strings;
		import io.shardingjdbc.core.exception.ShardingJdbcException;
		import io.shardingjdbc.core.rewrite.placeholder.IndexPlaceholder;
		import io.shardingjdbc.core.rewrite.placeholder.SchemaPlaceholder;
		import io.shardingjdbc.core.rewrite.placeholder.ShardingPlaceholder;
		import io.shardingjdbc.core.rewrite.placeholder.TablePlaceholder;
		import io.shardingjdbc.core.rule.ShardingRule;
		import io.shardingjdbc.core.rule.TableRule;
		import lombok.RequiredArgsConstructor;

		import java.util.LinkedList;
		import java.util.List;
		@@ -58,10 +61,10 @@ public final class SQLBuilder {
		/**
		* Append table token.
		*
		* @param tableName table name
		* @param logicTableName logic table name
		*/
		public void appendTable(final String tableName) {
		segments.add(new TableToken(tableName));
		public void appendTable(final String logicTableName) {
		segments.add(new TablePlaceholder(logicTableName));
		currentSegment = new StringBuilder();
		segments.add(currentSegment);
		}
		@@ -69,11 +72,11 @@ public final class SQLBuilder {
		/**
		* Append schema token.
		*
		* @param schemaName schema name
		* @param tableName table name
		* @param logicSchemaName logic schema name
		* @param logicTableName logic table name
		*/
		public void appendSchema(final String schemaName, final String tableName) {
		segments.add(new SchemaToken(schemaName, tableName));
		public void appendSchema(final String logicSchemaName, final String logicTableName) {
		segments.add(new SchemaPlaceholder(logicSchemaName, logicTableName));
		currentSegment = new StringBuilder();
		segments.add(currentSegment);
		}
		@@ -81,11 +84,11 @@ public final class SQLBuilder {
		/**
		* Append index token.
		*
		* @param indexName index name
		* @param tableName table name
		* @param logicIndexName logic index name
		* @param logicTableName logic table name
		*/
		public void appendIndex(final String indexName, final String tableName) {
		segments.add(new IndexToken(indexName, tableName));
		public void appendIndex(final String logicIndexName, final String logicTableName) {
		segments.add(new IndexPlaceholder(logicIndexName, logicTableName));
		currentSegment = new StringBuilder();
		segments.add(currentSegment);
		}
		@@ -100,23 +103,26 @@ public final class SQLBuilder {
		public String toSQL(final Map<String, String> logicAndActualTableMap, final ShardingRule shardingRule) {
		StringBuilder result = new StringBuilder();
		for (Object each : segments) {
		if (each instanceof TableToken && logicAndActualTableMap.containsKey(((TableToken) each).tableName)) {
		result.append(logicAndActualTableMap.get(((TableToken) each).tableName));
		} else if (each instanceof SchemaToken) {
		SchemaToken schemaToken = (SchemaToken) each;
		String actualTableName = logicAndActualTableMap.get(schemaToken.tableName);
		if (!(each instanceof ShardingPlaceholder)) {
		result.append(each);
		continue;
		}
		String logicTableName = ((ShardingPlaceholder) each).getLogicTableName();
		String actualTableName = logicAndActualTableMap.get(logicTableName);
		if (each instanceof TablePlaceholder) {
		result.append(null == actualTableName ? logicTableName : actualTableName);
		} else if (each instanceof SchemaPlaceholder) {
		SchemaPlaceholder schemaPlaceholder = (SchemaPlaceholder) each;
		Optional<TableRule> tableRule = shardingRule.tryFindTableRuleByActualTable(actualTableName);
		if (!tableRule.isPresent() && Strings.isNullOrEmpty(shardingRule.getDefaultDataSourceName())) {
		throw new ShardingJdbcException("Cannot found schema name '%s' in sharding rule.", schemaToken.schemaName);
		throw new ShardingJdbcException("Cannot found schema name '%s' in sharding rule.", schemaPlaceholder.getLogicSchemaName());
		}
		String actualDataSourceName = tableRule.get().getActualDatasourceNames().iterator().next();
		// TODO 目前只能找到真实数据源名称. 未来需要在初始化sharding rule时创建connnection,并验证连接是否正确,并获取出真实的schema的名字, 然后在这里替换actualDataSourceName为actualSchemaName
		// TODO 目前actualDataSourceName必须actualSchemaName一样,才能保证替换schema的场景不出错, 如: show columns xxx
		result.append(actualDataSourceName);
		} else if (each instanceof IndexToken) {
		IndexToken indexToken = (IndexToken) each;
		result.append(indexToken.indexName);
		String actualTableName = logicAndActualTableMap.get(indexToken.tableName);
		result.append(tableRule.get().getActualDatasourceNames().iterator().next());
		} else if (each instanceof IndexPlaceholder) {
		IndexPlaceholder indexPlaceholder = (IndexPlaceholder) each;
		result.append(indexPlaceholder.getLogicIndexName());
		if (!Strings.isNullOrEmpty(actualTableName)) {
		result.append("_");
		result.append(actualTableName);
		@@ -127,41 +133,4 @@ public final class SQLBuilder {
		}
		return result.toString();
		}

		@RequiredArgsConstructor
		private class TableToken {

		private final String tableName;

		@Override
		public String toString() {
		return tableName;
		}
		}

		@RequiredArgsConstructor
		private class SchemaToken {

		private final String schemaName;

		private final String tableName;

		@Override
		public String toString() {
		return schemaName;
		}
		}

		@RequiredArgsConstructor
		private class IndexToken {

		private final String indexName;

		private final String tableName;

		@Override
		public String toString() {
		return indexName;
		}
		}
		}

sharding-jdbc-core/src/main/java/io/shardingjdbc/core/rewrite/placeholder/SchemaPlaceholder.java

0 → 100644

+23 −0

Original line number	Diff line number	Diff line
		package io.shardingjdbc.core.rewrite.placeholder;

		import lombok.Getter;
		import lombok.RequiredArgsConstructor;

		/**
		* Schema placeholder for rewrite.
		*
		* @author zhangliang
		*/
		@RequiredArgsConstructor
		@Getter
		public final class SchemaPlaceholder implements ShardingPlaceholder {

		private final String logicSchemaName;

		private final String logicTableName;

		@Override
		public String toString() {
		return logicSchemaName;
		}
		}

sharding-jdbc-core/src/main/java/io/shardingjdbc/core/rewrite/placeholder/ShardingPlaceholder.java

0 → 100644

+16 −0

Original line number	Diff line number	Diff line
		package io.shardingjdbc.core.rewrite.placeholder;

		/**
		* Sharding placeholder for rewrite.
		*
		* @author zhangliang
		*/
		public interface ShardingPlaceholder {

		/**
		* Get logic table name.
		*
		* @return logic table name
		*/
		String getLogicTableName();
		}

sharding-jdbc-core/src/main/java/io/shardingjdbc/core/rewrite/placeholder/TablePlaceholder.java

0 → 100644

+21 −0

Original line number	Diff line number	Diff line
		package io.shardingjdbc.core.rewrite.placeholder;

		import lombok.Getter;
		import lombok.RequiredArgsConstructor;

		/**
		* Table placeholder for rewrite.
		*
		* @author zhangliang
		*/
		@RequiredArgsConstructor
		@Getter
		public final class TablePlaceholder implements ShardingPlaceholder {

		private final String logicTableName;

		@Override
		public String toString() {
		return logicTableName;
		}
		}