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#1021 enforce Checkstyle rules in the build

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Ilkka Seppälä
2019-11-16 16:00:24 +02:00
parent 9e58edf05e
commit 8747f1fd7a
17 changed files with 239 additions and 208 deletions
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85
role-object/src/main/java/com/iluwatar/roleobject/ApplicationRoleObject.java
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@ -20,13 +20,15 @@
* OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN
* THE SOFTWARE.
*/
package com.iluwatar.roleobject;
import static com.iluwatar.roleobject.Role.Borrower;
import static com.iluwatar.roleobject.Role.Investor;
import org.slf4j.Logger;
import org.slf4j.LoggerFactory;
import static com.iluwatar.roleobject.Role.*;
/**
* The Role Object pattern suggests to model context-specific views
* of an object as separate role objects which are
@ -39,55 +41,60 @@ import static com.iluwatar.roleobject.Role.*;
* investor, respectively. Both roles could as well be played by a single {@link Customer} object.
* The common superclass for customer-specific roles is provided by {@link CustomerRole},
* which also supports the {@link Customer} interface.
* <p>
* The {@link CustomerRole} class is abstract and not meant to be instantiated.
* Concrete subclasses of {@link CustomerRole}, for example {@link BorrowerRole} or {@link InvestorRole},
* define and implement the interface for specific roles. It is only
*
* <p>The {@link CustomerRole} class is abstract and not meant to be instantiated.
* Concrete subclasses of {@link CustomerRole}, for example {@link BorrowerRole}
* or {@link InvestorRole}, define and implement the interface for specific roles. It is only
* these subclasses which are instantiated at runtime.
* The {@link BorrowerRole} class defines the context-specific view of {@link Customer} objects as needed by the loan department.
* The {@link BorrowerRole} class defines the context-specific view of {@link Customer}
* objects as needed by the loan department.
* It defines additional operations to manage the customer’s
* credits and securities. Similarly, the {@link InvestorRole} class adds operations specific
* to the investment department’s view of customers.
* A client like the loan application may either work with objects of the {@link CustomerRole} class, using the interface class
* {@link Customer}, or with objects of concrete {@link CustomerRole} subclasses. Suppose the loan application knows a particular
* {@link Customer} instance through its {@link Customer} interface. The loan application may want to check whether the {@link Customer}
* object plays the role of Borrower.
* To this end it calls {@link Customer#hasRole(Role)} with a suitable role specification. For the purpose of
* our example, let’s assume we can name roles with enum.
* If the {@link Customer} object can play the role named “Borrower,” the loan application will ask it
* to return a reference to the corresponding object.
* A client like the loan application may either work with objects of the {@link CustomerRole}
* class, using the interface class {@link Customer}, or with objects of concrete
* {@link CustomerRole} subclasses. Suppose the loan application knows a particular
* {@link Customer} instance through its {@link Customer} interface. The loan application
* may want to check whether the {@link Customer} object plays the role of Borrower.
* To this end it calls {@link Customer#hasRole(Role)} with a suitable role specification. For
* the purpose of our example, let’s assume we can name roles with enum.
* If the {@link Customer} object can play the role named “Borrower,” the loan application will
* ask it to return a reference to the corresponding object.
* The loan application may now use this reference to call Borrower-specific operations.
*/
public class ApplicationRoleObject {
private static final Logger logger = LoggerFactory.getLogger(Role.class);
private static final Logger logger = LoggerFactory.getLogger(Role.class);
public static void main(String[] args) {
Customer customer = Customer.newCustomer(Borrower, Investor);
/**
* Main entry point.
*
* @param args program arguments
*/
public static void main(String[] args) {
Customer customer = Customer.newCustomer(Borrower, Investor);
logger.info(" the new customer created : {}", customer);
logger.info(" the new customer created : {}", customer);
boolean hasBorrowerRole = customer.hasRole(Borrower);
logger.info(" customer has a borrowed role - {}", hasBorrowerRole);
boolean hasInvestorRole = customer.hasRole(Investor);
logger.info(" customer has an investor role - {}", hasInvestorRole);
boolean hasBorrowerRole = customer.hasRole(Borrower);
logger.info(" customer has a borrowed role - {}", hasBorrowerRole);
boolean hasInvestorRole = customer.hasRole(Investor);
logger.info(" customer has an investor role - {}", hasInvestorRole);
customer.getRole(Investor, InvestorRole.class)
.ifPresent(inv -> {
inv.setAmountToInvest(1000);
inv.setName("Billy");
});
customer.getRole(Borrower, BorrowerRole.class)
.ifPresent(inv -> inv.setName("Johny"));
customer.getRole(Investor, InvestorRole.class)
.map(InvestorRole::invest)
.ifPresent(logger::info);
customer.getRole(Borrower, BorrowerRole.class)
.map(BorrowerRole::borrow)
.ifPresent(logger::info);
}
customer.getRole(Investor, InvestorRole.class)
.ifPresent(inv -> {
inv.setAmountToInvest(1000);
inv.setName("Billy");
});
customer.getRole(Borrower, BorrowerRole.class)
.ifPresent(inv -> inv.setName("Johny"));
customer.getRole(Investor, InvestorRole.class)
.map(InvestorRole::invest)
.ifPresent(logger::info);
customer.getRole(Borrower, BorrowerRole.class)
.map(BorrowerRole::borrow)
.ifPresent(logger::info);
}
}

24
role-object/src/main/java/com/iluwatar/roleobject/BorrowerRole.java
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@ -20,21 +20,23 @@
* OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN
* THE SOFTWARE.
*/
package com.iluwatar.roleobject;
public class BorrowerRole extends CustomerRole{
private String name;
public class BorrowerRole extends CustomerRole {
public String getName() {
return name;
}
private String name;
public void setName(String name) {
this.name = name;
}
public String getName() {
return name;
}
public String borrow(){
return String.format("Borrower %s wants to get some money.",name);
}
public void setName(String name) {
this.name = name;
}
public String borrow() {
return String.format("Borrower %s wants to get some money.", name);
}
}

80
role-object/src/main/java/com/iluwatar/roleobject/Customer.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.roleobject;
import java.util.Optional;
@ -29,51 +30,52 @@ import java.util.Optional;
*/
public abstract class Customer {
/**
* Add specific role @see {@link Role}
*
* @param role to add
* @return true if the operation has been successful otherwise false
*/
public abstract boolean addRole(Role role);
/**
* Add specific role @see {@link Role}.
* @param role to add
* @return true if the operation has been successful otherwise false
*/
public abstract boolean addRole(Role role);
/**
* Check specific role @see {@link Role}
*
* @param role to check
* @return true if the role exists otherwise false
*/
/**
* Check specific role @see {@link Role}.
* @param role to check
* @return true if the role exists otherwise false
*/
public abstract boolean hasRole(Role role);
public abstract boolean hasRole(Role role);
/**
* Remove specific role @see {@link Role}
*
* @param role to remove
* @return true if the operation has been successful otherwise false
*/
public abstract boolean remRole(Role role);
/**
* Remove specific role @see {@link Role}.
* @param role to remove
* @return true if the operation has been successful otherwise false
*/
public abstract boolean remRole(Role role);
/**
* Get specific instance associated with this role @see {@link Role}
*
* @param role to get
* @param expectedRole instance class expected to get
* @return optional with value if the instance exists and corresponds expected class
*/
public abstract <T extends Customer> Optional<T> getRole(Role role, Class<T> expectedRole);
/**
* Get specific instance associated with this role @see {@link Role}.
* @param role to get
* @param expectedRole instance class expected to get
* @return optional with value if the instance exists and corresponds expected class
*/
public abstract <T extends Customer> Optional<T> getRole(Role role, Class<T> expectedRole);
public static Customer newCustomer() {
return new CustomerCore();
}
public static Customer newCustomer(Role... role) {
Customer customer = newCustomer();
for (Role r : role) {
customer.addRole(r);
}
return customer;
public static Customer newCustomer() {
return new CustomerCore();
}
/**
* Create {@link Customer} with given roles.
* @param role roles
* @return Customer
*/
public static Customer newCustomer(Role... role) {
Customer customer = newCustomer();
for (Role r : role) {
customer.addRole(r);
}
return customer;
}
}

80
role-object/src/main/java/com/iluwatar/roleobject/CustomerCore.java
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@ -20,56 +20,60 @@
* OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN
* THE SOFTWARE.
*/
package com.iluwatar.roleobject;
import java.util.*;
import java.util.Arrays;
import java.util.HashMap;
import java.util.Map;
import java.util.Objects;
import java.util.Optional;
/**
* Core class to store different customer roles
* Core class to store different customer roles.
*
* @see CustomerRole
* Note: not thread safe
* @see CustomerRole Note: not thread safe
*/
public class CustomerCore extends Customer {
private Map<Role, CustomerRole> roles;
private Map<Role, CustomerRole> roles;
public CustomerCore() {
roles = new HashMap<>();
}
public CustomerCore() {
roles = new HashMap<>();
}
@Override
public boolean addRole(Role role) {
return role
.instance()
.map(inst -> {
roles.put(role, inst);
return true;
})
.orElse(false);
}
@Override
public boolean addRole(Role role) {
return role
.instance()
.map(inst -> {
roles.put(role, inst);
return true;
})
.orElse(false);
}
@Override
public boolean hasRole(Role role) {
return roles.containsKey(role);
}
@Override
public boolean hasRole(Role role) {
return roles.containsKey(role);
}
@Override
public boolean remRole(Role role) {
return Objects.nonNull(roles.remove(role));
}
@Override
public boolean remRole(Role role) {
return Objects.nonNull(roles.remove(role));
}
@Override
public <T extends Customer> Optional<T> getRole(Role role, Class<T> expectedRole) {
return Optional
.ofNullable(roles.get(role))
.filter(expectedRole::isInstance)
.map(expectedRole::cast);
}
@Override
public <T extends Customer> Optional<T> getRole(Role role, Class<T> expectedRole) {
return Optional
.ofNullable(roles.get(role))
.filter(expectedRole::isInstance)
.map(expectedRole::cast);
}
@Override
public String toString() {
String roles = Arrays.toString(this.roles.keySet().toArray());
return "Customer{roles=" + roles + "}";
}
@Override
public String toString() {
String roles = Arrays.toString(this.roles.keySet().toArray());
return "Customer{roles=" + roles + "}";
}
}

6
role-object/src/main/java/com/iluwatar/roleobject/CustomerRole.java
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@ -20,9 +20,11 @@
* OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN
* THE SOFTWARE.
*/
package com.iluwatar.roleobject;
/**
* Key abstraction for segregated roles
* Key abstraction for segregated roles.
*/
public abstract class CustomerRole extends CustomerCore{}
public abstract class CustomerRole extends CustomerCore{
}

37
role-object/src/main/java/com/iluwatar/roleobject/InvestorRole.java
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@ -20,29 +20,32 @@
* OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN
* THE SOFTWARE.
*/
package com.iluwatar.roleobject;
public class InvestorRole extends CustomerRole {
private String name;
private long amountToInvest;
public String getName() {
return name;
}
private String name;
public void setName(String name) {
this.name = name;
}
private long amountToInvest;
public long getAmountToInvest() {
return amountToInvest;
}
public String getName() {
return name;
}
public void setAmountToInvest(long amountToInvest) {
this.amountToInvest = amountToInvest;
}
public void setName(String name) {
this.name = name;
}
public String invest() {
return String.format("Investor %s has invested %d dollars", name, amountToInvest);
}
public long getAmountToInvest() {
return amountToInvest;
}
public void setAmountToInvest(long amountToInvest) {
this.amountToInvest = amountToInvest;
}
public String invest() {
return String.format("Investor %s has invested %d dollars", name, amountToInvest);
}
}

45
role-object/src/main/java/com/iluwatar/roleobject/Role.java
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@ -20,36 +20,41 @@
* OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN
* THE SOFTWARE.
*/
package com.iluwatar.roleobject;
import java.util.Optional;
import org.slf4j.Logger;
import org.slf4j.LoggerFactory;
import java.util.Optional;
/**
* Possible roles
* Possible roles.
*/
public enum Role {
Borrower(BorrowerRole.class), Investor(InvestorRole.class);
private Class<? extends CustomerRole> typeCst;
Borrower(BorrowerRole.class), Investor(InvestorRole.class);
Role(Class<? extends CustomerRole> typeCst) {
this.typeCst = typeCst;
}
private static final Logger logger = LoggerFactory.getLogger(Role.class);
@SuppressWarnings("unchecked")
public <T extends CustomerRole> Optional<T> instance() {
Class<? extends CustomerRole> typeCst = this.typeCst;
try {
return (Optional<T>) Optional.of(typeCst.newInstance());
} catch (InstantiationException | IllegalAccessException e) {
logger.error("error creating an object", e);
}
return Optional.empty();
private Class<? extends CustomerRole> typeCst;
Role(Class<? extends CustomerRole> typeCst) {
this.typeCst = typeCst;
}
private static final Logger logger = LoggerFactory.getLogger(Role.class);
/**
* Get instance.
*/
@SuppressWarnings("unchecked")
public <T extends CustomerRole> Optional<T> instance() {
Class<? extends CustomerRole> typeCst = this.typeCst;
try {
return (Optional<T>) Optional.of(typeCst.newInstance());
} catch (InstantiationException | IllegalAccessException e) {
logger.error("error creating an object", e);
}
return Optional.empty();
}
}