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本文主要研究一下sharding-jdbc的ShardingMasterSlaveRouter
ShardingMasterSlaveRouter
incubator-shardingsphere-4.0.0-RC1/sharding-core/sharding-core-route/src/main/java/org/apache/shardingsphere/core/route/router/masterslave/ShardingMasterSlaveRouter.java
@RequiredArgsConstructor
public final class ShardingMasterSlaveRouter {
private final Collection<MasterSlaveRule> masterSlaveRules;
/**
* Route Master slave after sharding.
*
* @param sqlRouteResult SQL route result
* @return route result
*/
public SQLRouteResult route(final SQLRouteResult sqlRouteResult) {
for (MasterSlaveRule each : masterSlaveRules) {
route(each, sqlRouteResult);
}
return sqlRouteResult;
}
private void route(final MasterSlaveRule masterSlaveRule, final SQLRouteResult sqlRouteResult) {
Collection<TableUnit> toBeRemoved = new LinkedList<>();
Collection<TableUnit> toBeAdded = new LinkedList<>();
for (TableUnit each : sqlRouteResult.getRoutingResult().getTableUnits().getTableUnits()) {
if (!masterSlaveRule.getName().equalsIgnoreCase(each.getDataSourceName())) {
continue;
}
toBeRemoved.add(each);
String actualDataSourceName;
if (isMasterRoute(sqlRouteResult.getSqlStatement().getType())) {
MasterVisitedManager.setMasterVisited();
actualDataSourceName = masterSlaveRule.getMasterDataSourceName();
} else {
actualDataSourceName = masterSlaveRule.getLoadBalanceAlgorithm().getDataSource(
masterSlaveRule.getName(), masterSlaveRule.getMasterDataSourceName(), new ArrayList<>(masterSlaveRule.getSlaveDataSourceNames()));
}
toBeAdded.add(createNewTableUnit(actualDataSourceName, each));
}
sqlRouteResult.getRoutingResult().getTableUnits().getTableUnits().removeAll(toBeRemoved);
sqlRouteResult.getRoutingResult().getTableUnits().getTableUnits().addAll(toBeAdded);
}
private boolean isMasterRoute(final SQLType sqlType) {
return SQLType.DQL != sqlType || MasterVisitedManager.isMasterVisited() || HintManager.isMasterRouteOnly();
}
private TableUnit createNewTableUnit(final String actualDataSourceName, final TableUnit originalTableUnit) {
TableUnit result = new TableUnit(actualDataSourceName, originalTableUnit.getDataSourceName());
result.getRoutingTables().addAll(originalTableUnit.getRoutingTables());
return result;
}
}
- ShardingMasterSlaveRouter提供了route方法，返回sqlRouteResult，这里修改了sqlRouteResult的routingResult的tableUnits的TableUnit集合
SQLRouteResult
incubator-shardingsphere-4.0.0-RC1/sharding-core/sharding-core-route/src/main/java/org/apache/shardingsphere/core/route/SQLRouteResult.java
@RequiredArgsConstructor
@Getter
@Setter
public final class SQLRouteResult {
private final SQLStatement sqlStatement;
private final GeneratedKey generatedKey;
// For multiple thread read cached sqlStatement, clone limit on SQLRouteResult, because limit will be modified after cache
// TODO need more good design here
private Limit limit;
private RoutingResult routingResult;
private OptimizeResult optimizeResult;
private final Collection<RouteUnit> routeUnits = new LinkedHashSet<>();
public SQLRouteResult(final SQLStatement sqlStatement) {
this(sqlStatement, null);
}
}
- SQLRouteResult拥有RoutingResult属性
RoutingResult
incubator-shardingsphere-4.0.0-RC1/sharding-core/sharding-core-route/src/main/java/org/apache/shardingsphere/core/route/type/RoutingResult.java
@Getter
public class RoutingResult {
private final TableUnits tableUnits = new TableUnits();
/**
* Judge is route for single database and table only or not.
*
* @return is route for single database and table only or not
*/
public boolean isSingleRouting() {
return 1 == tableUnits.getTableUnits().size();
}
}
- RoutingResult拥有TableUnits属性
TableUnits
incubator-shardingsphere-4.0.0-RC1/sharding-core/sharding-core-route/src/main/java/org/apache/shardingsphere/core/route/type/TableUnits.java
@Getter
@ToString
public final class TableUnits {
private final Collection<TableUnit> tableUnits = new LinkedHashSet<>();
/**
* Get all data source names.
*
* @return all data source names
*/
public Collection<String> getDataSourceNames() {
Collection<String> result = new HashSet<>(tableUnits.size(), 1);
for (TableUnit each : tableUnits) {
result.add(each.getDataSourceName());
}
return result;
}
/**
* Get routing table via data source name and actual table name.
*
* @param dataSourceName data source name
* @param actualTableName actual table name
* @return routing table
*/
public Optional<RoutingTable> getRoutingTable(final String dataSourceName, final String actualTableName) {
for (TableUnit each : tableUnits) {
Optional<RoutingTable> result = each.getRoutingTable(dataSourceName, actualTableName);
if (result.isPresent()) {
return result;
}
}
return Optional.absent();
}
/**
* Get actual tables group via data source name and logic tables' names.
* <p>
* Actual tables in same group are belong one logic name.
* </p>
*
* @param dataSourceName data source name
* @param logicTableNames logic tables' names
* @return actual tables group
*/
public List<Set<String>> getActualTableNameGroups(final String dataSourceName, final Set<String> logicTableNames) {
List<Set<String>> result = new ArrayList<>();
for (String logicTableName : logicTableNames) {
Set<String> actualTableNames = getActualTableNames(dataSourceName, logicTableName);
if (!actualTableNames.isEmpty()) {
result.add(actualTableNames);
}
}
return result;
}
private Set<String> getActualTableNames(final String dataSourceName, final String logicTableName) {
Set<String> result = new HashSet<>(tableUnits.size(), 1);
for (TableUnit each : tableUnits) {
result.addAll(each.getActualTableNames(dataSourceName, logicTableName));
}
return result;
}
/**
* Get map relationship between data source and logic tables via data sources' names.
*
* @param dataSourceNames data sources' names
* @return map relationship between data source and logic tables
*/
public Map<String, Set<String>> getDataSourceLogicTablesMap(final Collection<String> dataSourceNames) {
Map<String, Set<String>> result = new HashMap<>();
for (String each : dataSourceNames) {
Set<String> logicTableNames = getLogicTableNames(each);
if (!logicTableNames.isEmpty()) {
result.put(each, logicTableNames);
}
}
return result;
}
private Set<String> getLogicTableNames(final String dataSourceName) {
Set<String> result = new HashSet<>(tableUnits.size(), 1);
for (TableUnit each : tableUnits) {
if (each.getDataSourceName().equalsIgnoreCase(dataSourceName)) {
result.addAll(each.getLogicTableNames(dataSourceName));
}
}
return result;
}
}
- TableUnits内部是TableUnit的集合
TableUnit
incubator-shardingsphere-4.0.0-RC1/sharding-core/sharding-core-route/src/main/java/org/apache/shardingsphere/core/route/type/TableUnit.java
@RequiredArgsConstructor
@Getter
@EqualsAndHashCode
@ToString
public final class TableUnit {
private final String dataSourceName;
private final String masterSlaveLogicDataSourceName;
private final List<RoutingTable> routingTables = new LinkedList<>();
public TableUnit(final String dataSourceName) {
this.dataSourceName = dataSourceName;
masterSlaveLogicDataSourceName = dataSourceName;
}
/**
* Get routing table via data source name and actual table name.
*
* @param dataSourceName data source name
* @param actualTableName actual table name
* @return routing table
*/
public Optional<RoutingTable> getRoutingTable(final String dataSourceName, final String actualTableName) {
for (RoutingTable each : routingTables) {
if (dataSourceName.equalsIgnoreCase(masterSlaveLogicDataSourceName) && each.getActualTableName().equalsIgnoreCase(actualTableName)) {
return Optional.of(each);
}
}
return Optional.absent();
}
/**
* Get actual tables' names via data source name.
*
* @param dataSourceName data source name
* @param logicTableName logic table name
* @return actual tables' names
*/
public Set<String> getActualTableNames(final String dataSourceName, final String logicTableName) {
Set<String> result = new HashSet<>(routingTables.size(), 1);
for (RoutingTable each : routingTables) {
if (dataSourceName.equalsIgnoreCase(this.dataSourceName) && each.getLogicTableName().equalsIgnoreCase(logicTableName)) {
result.add(each.getActualTableName());
}
}
return result;
}
/**
* Get logic tables' names via data source name.
*
* @param dataSourceName data source name
* @return logic tables' names
*/
public Set<String> getLogicTableNames(final String dataSourceName) {
Set<String> result = new HashSet<>(routingTables.size(), 1);
for (RoutingTable each : routingTables) {
if (dataSourceName.equalsIgnoreCase(this.dataSourceName)) {
result.add(each.getLogicTableName());
}
}
return result;
}
}
- TableUnit包含了RoutingTable的集合
RoutingTable
incubator-shardingsphere-4.0.0-RC1/sharding-core/sharding-core-route/src/main/java/org/apache/shardingsphere/core/route/type/RoutingTable.java
@RequiredArgsConstructor
@Getter
@EqualsAndHashCode
@ToString
public final class RoutingTable {
private final String logicTableName;
private final String actualTableName;
}
- RoutingTable包含了logicTableName与actualTableName
小结
ShardingMasterSlaveRouter提供了route方法，返回sqlRouteResult，这里修改了sqlRouteResult的routingResult的tableUnits的TableUnit集合
