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add changes according to google style

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This commit is contained in:
Besok 2019-11-13 21:01:10 +00:00
parent de56cbb971
commit 87af122509
20 changed files with 98 additions and 62 deletions
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4
saga/src/main/java/com/iluwatar/saga/choreography/ChoreographyChapter.java
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@ -20,6 +20,7 @@
* OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN
* THE SOFTWARE.
*/
package com.iluwatar.saga.choreography;
@ -31,7 +32,7 @@ package com.iluwatar.saga.choreography;
public interface ChoreographyChapter {
/**
* In that case, every method is responsible to make a decision on what to do then
* In that case, every method is responsible to make a decision on what to do then.
*
* @param saga incoming saga
* @return saga result
@ -39,6 +40,7 @@ public interface ChoreographyChapter {
Saga execute(Saga saga);
/**
* get name method.
* @return service name.
*/
String getName();

3
saga/src/main/java/com/iluwatar/saga/choreography/FlyBookingService.java
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@ -20,11 +20,12 @@
* OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN
* THE SOFTWARE.
*/
package com.iluwatar.saga.choreography;
/**
* Class representing a service to book a fly
* Class representing a service to book a fly.
*/
public class FlyBookingService extends Service {
public FlyBookingService(ServiceDiscoveryService service) {

3
saga/src/main/java/com/iluwatar/saga/choreography/HotelBookingService.java
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@ -20,11 +20,12 @@
* OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN
* THE SOFTWARE.
*/
package com.iluwatar.saga.choreography;
/**
* Class representing a service to book a hotel
* Class representing a service to book a hotel.
*/
public class HotelBookingService extends Service {
public HotelBookingService(ServiceDiscoveryService service) {

1
saga/src/main/java/com/iluwatar/saga/choreography/OrderService.java
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@ -20,6 +20,7 @@
* OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN
* THE SOFTWARE.
*/
package com.iluwatar.saga.choreography;

26
saga/src/main/java/com/iluwatar/saga/choreography/Saga.java
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@ -20,6 +20,7 @@
* OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN
* THE SOFTWARE.
*/
package com.iluwatar.saga.choreography;
import java.util.ArrayList;
@ -44,7 +45,7 @@ public class Saga {
}
/**
* get resuzlt of saga
* get resuzlt of saga.
*
* @return result of saga @see {@link SagaResult}
*/
@ -59,7 +60,7 @@ public class Saga {
}
/**
* add chapter to saga
* add chapter to saga.
* @param name chapter name
* @return this
*/
@ -69,7 +70,7 @@ public class Saga {
}
/**
* set value to last chapter
* set value to last chapter.
* @param value invalue
* @return this
*/
@ -82,7 +83,7 @@ public class Saga {
}
/**
* get value from current chapter
* get value from current chapter.
* @return value
*/
public Object getCurrentValue() {
@ -90,7 +91,7 @@ public class Saga {
}
/**
* set value to current chapter
* set value to current chapter.
* @param value to set
*/
public void setCurrentValue(Object value) {
@ -98,7 +99,7 @@ public class Saga {
}
/**
* set status for current chapter
* set status for current chapter.
* @param result to set
*/
public void setCurrentStatus(ChapterResult result) {
@ -143,8 +144,9 @@ public class Saga {
return chapters.get(pos).isSuccess();
}
/***
* Class presents a chapter status and incoming parameters(incoming parameter transforms to outcoming parameter)
/**
* Class presents a chapter status and incoming
* parameters(incoming parameter transforms to outcoming parameter).
*/
public static class Chapter {
private String name;
@ -170,7 +172,7 @@ public class Saga {
}
/**
* set result
* set result.
* @param result {@link ChapterResult}
*/
public void setResult(ChapterResult result) {
@ -178,7 +180,7 @@ public class Saga {
}
/**
* the result for chapter is good
* the result for chapter is good.
* @return true if is good otherwise bad
*/
public boolean isSuccess() {
@ -188,14 +190,14 @@ public class Saga {
/**
* result for chapter
* result for chapter.
*/
public enum ChapterResult {
INIT, SUCCESS, ROLLBACK
}
/**
* result for saga
* result for saga.
*/
public enum SagaResult {
PROGRESS, FINISHED, ROLLBACKED

26
saga/src/main/java/com/iluwatar/saga/choreography/SagaApplication.java
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@ -20,25 +20,29 @@
* OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN
* THE SOFTWARE.
*/
package com.iluwatar.saga.choreography;
package com.iluwatar.saga.choreography;
import org.slf4j.Logger;
import org.slf4j.LoggerFactory;
/**
* This pattern is used in distributed services to perform a group of operations atomically.
* This is an analog of transaction in a database but in terms of microservices architecture this is executed
* This is an analog of transaction in a database but in terms
* of microservices architecture this is executed
* in a distributed environment
* <p>
* A saga is a sequence of local transactions in a certain context. If one transaction fails for some reason,
* the saga executes compensating transactions(rollbacks) to undo the impact of the preceding transactions.
* <p>
* In this approach, there are no mediators or orchestrators services.
*
* <p>A saga is a sequence of local transactions in a certain context.
* If one transaction fails for some reason,
* the saga executes compensating transactions(rollbacks)
* to undo the impact of the preceding transactions.
*
* <p>In this approach, there are no mediators or orchestrators services.
* All chapters are handled and moved by services manually.
* <p>
* The major difference with choreography saga is an ability to handle crashed services
* (otherwise in choreography services very hard to prevent a saga if one of them has been crashed)
*
* <p>The major difference with choreography saga is an ability to handle crashed services
* (otherwise in choreography services very hard to prevent a saga
* if one of them has been crashed)
*
* @see com.iluwatar.saga.choreography.Saga
* @see Service
@ -47,7 +51,7 @@ public class SagaApplication {
private static final Logger LOGGER = LoggerFactory.getLogger(SagaApplication.class);
/**
* main method
* main method.
*/
public static void main(String[] args) {
ServiceDiscoveryService sd = serviceDiscovery();

14
saga/src/main/java/com/iluwatar/saga/choreography/Service.java
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@ -20,15 +20,16 @@
* OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN
* THE SOFTWARE.
*/
package com.iluwatar.saga.choreography;
import java.util.function.Supplier;
import org.slf4j.Logger;
import org.slf4j.LoggerFactory;
import java.util.function.Supplier;
/**
* Common abstraction class representing services
* Common abstraction class representing services.
* implementing a general contract @see {@link ChoreographyChapter}
*/
public abstract class Service implements ChoreographyChapter {
@ -73,13 +74,15 @@ public abstract class Service implements ChoreographyChapter {
}
private Supplier<RuntimeException> serviceNotFoundException(String chServiceName) {
return () -> new RuntimeException(String.format("the service %s has not been found", chServiceName));
return () -> new RuntimeException(
String.format("the service %s has not been found", chServiceName));
}
@Override
public Saga process(Saga saga) {
Object inValue = saga.getCurrentValue();
LOGGER.info("The chapter '{}' has been started. The data {} has been stored or calculated successfully",
LOGGER.info("The chapter '{}' has been started. "
+ "The data {} has been stored or calculated successfully",
getName(), inValue);
saga.setCurrentStatus(Saga.ChapterResult.SUCCESS);
saga.setCurrentValue(inValue);
@ -89,7 +92,8 @@ public abstract class Service implements ChoreographyChapter {
@Override
public Saga rollback(Saga saga) {
Object inValue = saga.getCurrentValue();
LOGGER.info("The Rollback for a chapter '{}' has been started. The data {} has been rollbacked successfully",
LOGGER.info("The Rollback for a chapter '{}' has been started. "
+ "The data {} has been rollbacked successfully",
getName(), inValue);
saga.setCurrentStatus(Saga.ChapterResult.ROLLBACK);

4
saga/src/main/java/com/iluwatar/saga/choreography/ServiceDiscoveryService.java
View File

@ -20,8 +20,8 @@
* OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN
* THE SOFTWARE.
*/
package com.iluwatar.saga.choreography;
package com.iluwatar.saga.choreography;
import java.util.HashMap;
import java.util.Map;
@ -35,7 +35,7 @@ public class ServiceDiscoveryService {
private Map<String, ChoreographyChapter> services;
/**
* find any service
* find any service.
*
* @return any service
* @throws NoSuchElementException if no elements further

4
saga/src/main/java/com/iluwatar/saga/choreography/WithdrawMoneyService.java
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@ -20,11 +20,11 @@
* OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN
* THE SOFTWARE.
*/
package com.iluwatar.saga.choreography;
/**
* Class representing a service to withdraw a money
* Class representing a service to withdraw a money.
*/
public class WithdrawMoneyService extends Service {

5
saga/src/main/java/com/iluwatar/saga/orchestration/ChapterResult.java
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@ -20,10 +20,11 @@
* OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN
* THE SOFTWARE.
*/
package com.iluwatar.saga.orchestration;
/**
* Executing result for chapter
* Executing result for chapter.
*
* @param <K> incoming value
*/
@ -53,7 +54,7 @@ public class ChapterResult<K> {
}
/**
* state for chapter
* state for chapter.
*/
public enum State {
SUCCESS, FAILURE

3
saga/src/main/java/com/iluwatar/saga/orchestration/FlyBookingService.java
View File

@ -20,10 +20,11 @@
* OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN
* THE SOFTWARE.
*/
package com.iluwatar.saga.orchestration;
/**
* Class representing a service to book a fly
* Class representing a service to book a fly.
*/
public class FlyBookingService extends Service<String> {
@Override

6
saga/src/main/java/com/iluwatar/saga/orchestration/HotelBookingService.java
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@ -20,10 +20,11 @@
* OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN
* THE SOFTWARE.
*/
package com.iluwatar.saga.orchestration;
/**
* Class representing a service to book a hotel
* Class representing a service to book a hotel.
*/
public class HotelBookingService extends Service<String> {
@Override
@ -42,7 +43,8 @@ public class HotelBookingService extends Service<String> {
return ChapterResult.failure(value);
}
LOGGER.info("The Rollback for a chapter '{}' has been started. The data {} has been rollbacked successfully",
LOGGER.info("The Rollback for a chapter '{}' has been started. "
+ "The data {} has been rollbacked successfully",
getName(), value);
return super.rollback(value);

2
saga/src/main/java/com/iluwatar/saga/orchestration/OrchestrationChapter.java
View File

@ -20,6 +20,7 @@
* OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN
* THE SOFTWARE.
*/
package com.iluwatar.saga.orchestration;
/**
@ -30,6 +31,7 @@ package com.iluwatar.saga.orchestration;
public interface OrchestrationChapter<K> {
/**
* method get name.
* @return service name.
*/
String getName();

1
saga/src/main/java/com/iluwatar/saga/orchestration/OrderService.java
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@ -20,6 +20,7 @@
* OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN
* THE SOFTWARE.
*/
package com.iluwatar.saga.orchestration;
/**

5
saga/src/main/java/com/iluwatar/saga/orchestration/Saga.java
View File

@ -20,6 +20,7 @@
* OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN
* THE SOFTWARE.
*/
package com.iluwatar.saga.orchestration;
import java.util.ArrayList;
@ -60,14 +61,14 @@ public class Saga {
}
/**
* result for saga
* result for saga.
*/
public enum Result {
FINISHED, ROLLBACK, CRASHED
}
/**
* class represents chapter name
* class represents chapter name.
*/
public static class Chapter {
String name;

27
saga/src/main/java/com/iluwatar/saga/orchestration/SagaApplication.java
View File

@ -23,23 +23,27 @@
package com.iluwatar.saga.orchestration;
import org.slf4j.Logger;
import org.slf4j.LoggerFactory;
/**
* This pattern is used in distributed services to perform a group of operations atomically.
* This is an analog of transaction in a database but in terms of microservices architecture this is executed
* This pattern is used in distributed services to perform
* a group of operations atomically.
* This is an analog of transaction in a database but in terms
* of microservices architecture this is executed
* in a distributed environment
* <p>
* A saga is a sequence of local transactions in a certain context. If one transaction fails for some reason,
* the saga executes compensating transactions(rollbacks) to undo the impact of the preceding transactions.
* <p>
* In this approach, there is an orchestrator @see {@link SagaOrchestrator}
*
* <p>A saga is a sequence of local transactions in a certain context.
* If one transaction fails for some reason,
* the saga executes compensating transactions(rollbacks)
* to undo the impact of the preceding transactions.
*
* <p>In this approach, there is an orchestrator @see {@link SagaOrchestrator}
* that manages all the transactions and directs
* the participant services to execute local transactions based on events.
* The major difference with choreography saga is an ability to handle crashed services
* (otherwise in choreography services very hard to prevent a saga if one of them has been crashed)
* (otherwise in choreography services very hard to prevent a saga
* if one of them has been crashed)
*
* @see Saga
* @see SagaOrchestrator
@ -49,7 +53,7 @@ public class SagaApplication {
private static final Logger LOGGER = LoggerFactory.getLogger(SagaApplication.class);
/**
* method to show common saga logic
* method to show common saga logic.
*/
public static void main(String[] args) {
SagaOrchestrator sagaOrchestrator = new SagaOrchestrator(newSaga(), serviceDiscovery());
@ -58,7 +62,8 @@ public class SagaApplication {
Saga.Result badOrder = sagaOrchestrator.execute("bad_order");
Saga.Result crashedOrder = sagaOrchestrator.execute("crashed_order");
LOGGER.info("orders: goodOrder is {}, badOrder is {},crashedOrder is {}", goodOrder, badOrder, crashedOrder);
LOGGER.info("orders: goodOrder is {}, badOrder is {},crashedOrder is {}",
goodOrder, badOrder, crashedOrder);
}

13
saga/src/main/java/com/iluwatar/saga/orchestration/SagaOrchestrator.java
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@ -20,14 +20,17 @@
* OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN
* THE SOFTWARE.
*/
package com.iluwatar.saga.orchestration;
import static com.iluwatar.saga.orchestration.Saga.Result.CRASHED;
import static com.iluwatar.saga.orchestration.Saga.Result.FINISHED;
import static com.iluwatar.saga.orchestration.Saga.Result.ROLLBACK;
import java.util.Optional;
import org.slf4j.Logger;
import org.slf4j.LoggerFactory;
import java.util.Optional;
import static com.iluwatar.saga.orchestration.Saga.Result.*;
/**
* The orchestrator that manages all the transactions and directs
@ -41,7 +44,7 @@ public class SagaOrchestrator {
/**
* Create a new service to orchetrate sagas
* Create a new service to orchetrate sagas.
* @param saga saga to process
* @param sd service discovery @see {@link ServiceDiscoveryService}
*/
@ -52,7 +55,7 @@ public class SagaOrchestrator {
}
/**
* pipeline to execute saga process/story
* pipeline to execute saga process/story.
*
* @param value incoming value
* @param <K> type for incoming value

9
saga/src/main/java/com/iluwatar/saga/orchestration/Service.java
View File

@ -20,13 +20,14 @@
* OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN
* THE SOFTWARE.
*/
package com.iluwatar.saga.orchestration;
import org.slf4j.Logger;
import org.slf4j.LoggerFactory;
/**
* Common abstraction class representing services
* Common abstraction class representing services.
* implementing a general contract @see {@link OrchestrationChapter}
*
* @param <K> type of incoming param
@ -40,14 +41,16 @@ public abstract class Service<K> implements OrchestrationChapter<K> {
@Override
public ChapterResult<K> process(K value) {
LOGGER.info("The chapter '{}' has been started. The data {} has been stored or calculated successfully",
LOGGER.info("The chapter '{}' has been started. "
+ "The data {} has been stored or calculated successfully",
getName(), value);
return ChapterResult.success(value);
}
@Override
public ChapterResult<K> rollback(K value) {
LOGGER.info("The Rollback for a chapter '{}' has been started. The data {} has been rollbacked successfully",
LOGGER.info("The Rollback for a chapter '{}' has been started. "
+ "The data {} has been rollbacked successfully",
getName(), value);
return ChapterResult.success(value);
}

1
saga/src/main/java/com/iluwatar/saga/orchestration/ServiceDiscoveryService.java
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@ -20,6 +20,7 @@
* OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN
* THE SOFTWARE.
*/
package com.iluwatar.saga.orchestration;
import java.util.HashMap;

3
saga/src/main/java/com/iluwatar/saga/orchestration/WithdrawMoneyService.java
View File

@ -20,10 +20,11 @@
* OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN
* THE SOFTWARE.
*/
package com.iluwatar.saga.orchestration;
/**
* Class representing a service to withdraw a money
* Class representing a service to withdraw a money.
*/
public class WithdrawMoneyService extends Service<String> {
@Override