prepare for…

Functional-Reactive…with Core Java 8/9

@SvenRuppert has been coding java since 1996

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@SvenRuppert has been coding java since 1996

Projects in the field of:•Automobile-industry•Energy•Finance / Leasing•Space- Satellit-•Government / UN / World-bank

Where?

•Europe•Asia - from India up to Malaysia

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Small AddOns

based on Java8

@SvenRuppert

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@SvenRuppertJava8 - Optional<T>

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@SvenRuppertJava8 - Optional<T>

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@SvenRuppertJava8 - Optional<T>

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@SvenRuppertJava8 - Optional<T>

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@SvenRuppertJava8 - Optional<T>

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@SvenRuppertJava8 - Optional<T>

Optional - [ Int, Double, Long ]

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@SvenRuppertJava8 - Functional Interfaces

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@SvenRuppertJava8 - Functional Interfaces

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@SvenRuppertJava8 - Functional Interfaces

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@SvenRuppertJava8 - Functional Interfaces

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@SvenRuppertJava8 - Functional Interfaces

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@SvenRuppertJava8 - Functional Interfaces

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@SvenRuppertJava8 - Functional Interfaces

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@SvenRuppertJava8 - Functional Interfaces

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@SvenRuppertJava8 - Functional Interfaces

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@SvenRuppertJava8 - Functional Interfaces

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@SvenRuppertJava8 - Functional Interfaces

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@SvenRuppertJava8 - Functional Interfaces

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@SvenRuppertJava8 - Functional Interfaces

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@SvenRuppertJava8 - Functional Interfaces

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@SvenRuppertJava9 - Functional Interfaces

Java9 - JEP213

Functions

how use Functions…

@SvenRuppert

Functions - Java8

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@SvenRuppert

Functions - Java8

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@SvenRuppert

Functions - Java8

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@SvenRuppert

Functions - Java8

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@SvenRuppert

Functions - Java8

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@SvenRuppert

Functions - Java8

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@SvenRuppert

Functions - Java8

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@SvenRuppert

Functions - Java8

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@SvenRuppert

Functions - Java8

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@SvenRuppert

Functions - Java8

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@SvenRuppert

Functions - Java8

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@SvenRuppert

Functions - Java8

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@SvenRuppert

Functions - Java8

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@SvenRuppert

Functions - Java8

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@SvenRuppert

Functions - Java8

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@SvenRuppert

Functions - Java8

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@SvenRuppert

Functions - Java8

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@SvenRuppert

Functions - Java8

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@SvenRuppert

Functions - Java8

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@SvenRuppert

Functions - Java8

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@SvenRuppert

Functions - Java8

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@SvenRuppert

Functions - Java8

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@SvenRuppert

Functions - Java8

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@SvenRuppert

Functions - Java8

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@SvenRuppert

Functions - Java8

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@SvenRuppert

Functions - Java8

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@SvenRuppert

Functions - Java8

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@SvenRuppert

Functions - Java8

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@SvenRuppert

Functions - Java8

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@SvenRuppert

Refactoring example

based on Java8

@SvenRuppert

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@SvenRuppertJava8 - Functional Interfaces - Example

typical legacy implementation

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@SvenRuppertJava8 - Functional Interfaces - Example

typical legacy implementation

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@SvenRuppertJava8 - Functional Interfaces - Example

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@SvenRuppertJava8 - Functional Interfaces - Example

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@SvenRuppertJava8 - Functional Interfaces - Example

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@SvenRuppertJava8 - Functional Interfaces - Example

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@SvenRuppertJava8 - Functional Interfaces - Example

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@SvenRuppertJava8 - Functional Interfaces - Example

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@SvenRuppertJava8 - Functional Interfaces - Example

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@SvenRuppertJava8 - Functional Interfaces - Example

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@SvenRuppertJava8 - Functional Interfaces - Example

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@SvenRuppertJava8 - Functional Interfaces - Example

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@SvenRuppertJava8 - Functional Interfaces - Example

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@SvenRuppertJava8 - Functional Interfaces - Example

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@SvenRuppertJava8 - Functional Interfaces - Example

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@SvenRuppertJava8 - Functional Interfaces - Example

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@SvenRuppertJava8 - Functional Interfaces - Example

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@SvenRuppertJava8 - Functional Interfaces - Example

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@SvenRuppertJava8 - Functional Interfaces - Example

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@SvenRuppertJava8 - Functional Interfaces - Example

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@SvenRuppertJava8 - Functional Interfaces - Example

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@SvenRuppertJava8 - Functional Interfaces - Example

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@SvenRuppertJava8 - Functional Interfaces - Example

Sourcecode is on github

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@SvenRuppertJava8 - Functional Interfaces - Example

Sourcecode is on github

Pattern in Java 8/9

how pattern will change…

@SvenRuppert

Virtual Proxy

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@SvenRuppert

Virtual Proxy

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@SvenRuppert

public class ServiceProxy implements Service { private Service service = new ServiceImpl(); public String work(String txt) { return service.work(txt); }}

Virtual Proxy

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@SvenRuppert

public class ServiceProxy implements Service { private Service service = new ServiceImpl(); public String work(String txt) { return service.work(txt); }}

What could we

change now ?

Virtual Proxy

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@SvenRuppert

public class ServiceProxy implements Service { private Service service = new ServiceImpl(); public String work(String txt) { return service.work(txt); }}

What could we

change now ? Virtual Proxy:

create the Delegator later

Virtual Proxy

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@SvenRuppert

public class ServiceProxy implements Service { private Service service = new ServiceImpl(); public String work(String txt) { return service.work(txt); }}

What could we

change now ? Virtual Proxy:

create the Delegator later

public class VirtualService implements Service { private Service service = null; public String work(String txt) { if(service == null) { service = new ServiceImpl(); } return service.work(txt); }}

Virtual Proxy

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@SvenRuppert

public class ServiceProxy implements Service { private Service service = new ServiceImpl(); public String work(String txt) { return service.work(txt); }}

What could we

change now ? Virtual Proxy:

create the Delegator later

public class VirtualService implements Service { private Service service = null; public String work(String txt) { if(service == null) { service = new ServiceImpl(); } return service.work(txt); }}

Virtual Proxy

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@SvenRuppert

public class ServiceProxy implements Service { private Service service = new ServiceImpl(); public String work(String txt) { return service.work(txt); }}

What could we

change now ? Virtual Proxy:

create the Delegator later

public class VirtualService implements Service { private Service service = null; public String work(String txt) { if(service == null) { service = new ServiceImpl(); } return service.work(txt); }}

Virtual Proxy

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@SvenRuppert

public class VirtualService implements Service { private Service service = null; public String work(String txt) { if(service == null) { service = new ServiceImpl(); }

return service.work(txt); }}

Virtual Proxy

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@SvenRuppert

public class VirtualService implements Service { private Service service = null; public String work(String txt) { if(service == null) { service = new ServiceImpl(); }

return service.work(txt); }}

Virtual Proxy

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@SvenRuppert

public class VirtualService implements Service { private Service service = null; public String work(String txt) { if(service == null) { service = new ServiceImpl(); }

return service.work(txt); }}

This is NOT ThreadSafe

Virtual Proxy

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@SvenRuppert

public class VirtualService implements Service { private Service service = null; public String work(String txt) { if(service == null) { service = new ServiceImpl(); }

return service.work(txt); }}

This is NOT ThreadSafe

Virtual Proxy

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@SvenRuppert

public class VirtualService implements Service { private Service service = null; public String work(String txt) { if(service == null) { service = new ServiceImpl(); }

return service.work(txt); }}

This is NOT ThreadSafefixed decision for

an implementation

Virtual Proxy

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@SvenRuppert

public class VirtualService implements Service { private Service service = null; public String work(String txt) { if(service == null) { service = new ServiceImpl(); }

return service.work(txt); }}

This is NOT ThreadSafefixed decision for

an implementation

Virtual Proxy

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@SvenRuppert

public class VirtualService implements Service { private Service service = null; public String work(String txt) { if(service == null) { service = new ServiceImpl(); }

return service.work(txt); }}

This is NOT ThreadSafefixed decision for

an implementation

how to combine it with a FactoryPattern ?

Virtual Proxy

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@SvenRuppert

if(service == null) { service = new ServiceImpl(); }

Virtual Proxy

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@SvenRuppert

if(service == null) { service = new ServiceImpl(); }

Virtual Proxy

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@SvenRuppert

if(service == null) { service = new ServiceImpl(); }

public interface ServiceFactory { Service createInstance();}

Virtual Proxy

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@SvenRuppert

if(service == null) { service = new ServiceImpl(); }

public interface ServiceFactory { Service createInstance();}

Virtual Proxy

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@SvenRuppert

if(service == null) { service = new ServiceImpl(); }

public interface ServiceFactory { Service createInstance();}

public interface ServiceStrategyFactory { Service realSubject(ServiceFactory factory);}

Virtual Proxy - Not - ThreadSafe

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@SvenRuppert

if(service == null) { service = new ServiceImpl(); }

Virtual Proxy - Not - ThreadSafe

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@SvenRuppert

if(service == null) { service = new ServiceImpl(); }

Virtual Proxy - Not - ThreadSafe

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@SvenRuppert

if(service == null) { service = new ServiceImpl(); }

private ServiceFactory serviceFactory = ServiceImpl::new;

Virtual Proxy - Not - ThreadSafe

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@SvenRuppert

if(service == null) { service = new ServiceImpl(); }

private ServiceFactory serviceFactory = ServiceImpl::new;

Virtual Proxy - Not - ThreadSafe

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@SvenRuppert

if(service == null) { service = new ServiceImpl(); }

public class ServiceStrategyFactoryImpl implements ServiceStrategyFactory { Service realSubject; public Service realSubject(final ServiceFactory factory) { if (realSubject == null) { realSubject = factory.createInstance(); } return realSubject; }}

private ServiceFactory serviceFactory = ServiceImpl::new;

Virtual Proxy - Not - ThreadSafe

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@SvenRuppert

if(service == null) { service = new ServiceImpl(); }

Virtual Proxy - Not - ThreadSafe

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@SvenRuppert

if(service == null) { service = new ServiceImpl(); }

public class ServiceProxy implements Service {

Virtual Proxy - Not - ThreadSafe

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@SvenRuppert

if(service == null) { service = new ServiceImpl(); }

public class ServiceProxy implements Service {private ServiceFactory serviceFactory = ServiceImpl::new;

Virtual Proxy - Not - ThreadSafe

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@SvenRuppert

if(service == null) { service = new ServiceImpl(); }

public class ServiceProxy implements Service {private ServiceFactory serviceFactory = ServiceImpl::new;private ServiceStrategyFactory strategyFactory = new ServiceStrategyFactoryImpl();

Virtual Proxy - Not - ThreadSafe

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@SvenRuppert

if(service == null) { service = new ServiceImpl(); }

public class ServiceProxy implements Service {private ServiceFactory serviceFactory = ServiceImpl::new;private ServiceStrategyFactory strategyFactory = new ServiceStrategyFactoryImpl();

public String work(String txt) {

Virtual Proxy - Not - ThreadSafe

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@SvenRuppert

if(service == null) { service = new ServiceImpl(); }

public class ServiceProxy implements Service {private ServiceFactory serviceFactory = ServiceImpl::new;private ServiceStrategyFactory strategyFactory = new ServiceStrategyFactoryImpl();

public String work(String txt) {

}}

Virtual Proxy - Not - ThreadSafe

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@SvenRuppert

if(service == null) { service = new ServiceImpl(); }

public class ServiceProxy implements Service {private ServiceFactory serviceFactory = ServiceImpl::new;private ServiceStrategyFactory strategyFactory = new ServiceStrategyFactoryImpl();

public String work(String txt) {return

}}

Virtual Proxy - Not - ThreadSafe

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@SvenRuppert

if(service == null) { service = new ServiceImpl(); }

public class ServiceProxy implements Service {private ServiceFactory serviceFactory = ServiceImpl::new;private ServiceStrategyFactory strategyFactory = new ServiceStrategyFactoryImpl();

public String work(String txt) {return strategyFactory

}}

Virtual Proxy - Not - ThreadSafe

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@SvenRuppert

if(service == null) { service = new ServiceImpl(); }

public class ServiceProxy implements Service {private ServiceFactory serviceFactory = ServiceImpl::new;private ServiceStrategyFactory strategyFactory = new ServiceStrategyFactoryImpl();

public String work(String txt) {return strategyFactory .realSubject(

}}

Virtual Proxy - Not - ThreadSafe

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@SvenRuppert

if(service == null) { service = new ServiceImpl(); }

public class ServiceProxy implements Service {private ServiceFactory serviceFactory = ServiceImpl::new;private ServiceStrategyFactory strategyFactory = new ServiceStrategyFactoryImpl();

public String work(String txt) {return strategyFactory .realSubject(serviceFactory

}}

Virtual Proxy - Not - ThreadSafe

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@SvenRuppert

if(service == null) { service = new ServiceImpl(); }

public class ServiceProxy implements Service {private ServiceFactory serviceFactory = ServiceImpl::new;private ServiceStrategyFactory strategyFactory = new ServiceStrategyFactoryImpl();

public String work(String txt) {return strategyFactory .realSubject(serviceFactory).work(txt);

}}

Virtual Proxy - Show some code….

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@SvenRuppert

Virtual Proxy - Show some code….

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@SvenRuppert

Virtual Proxy - Show some code….

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@SvenRuppert

Virtual Proxy - Show some code….

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@SvenRuppert

Virtual Proxy - Show some code….

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@SvenRuppert

Virtual Proxy - Show some code….

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@SvenRuppert

Virtual Proxy - Show some code….

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@SvenRuppert

Virtual Proxy - Show some code….

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@SvenRuppert

Virtual Proxy - Show some code….

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@SvenRuppert

Virtual Proxy - Show some code….

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@SvenRuppert

Virtual Proxy - Show some code….

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@SvenRuppert

Virtual Proxy - Show some code….

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@SvenRuppert

Virtual Proxy - Show some code….

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@SvenRuppert

Virtual Proxy - Show some code….

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@SvenRuppert

Virtual Proxy - Show some code….

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@SvenRuppert

Virtual Proxy - Show some code….

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@SvenRuppert

Virtual Proxy - Show some code….

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@SvenRuppert

Virtual Proxy - Show some code….

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@SvenRuppert

Virtual Proxy - Show some code….

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@SvenRuppert

Virtual Proxy - Show some code….

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@SvenRuppert

Virtual Proxy - Show some code….

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@SvenRuppert

Virtual Proxy - Show some code….

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@SvenRuppert

Virtual Proxy - Show some code….

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@SvenRuppert

Virtual Proxy - Show some code….

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@SvenRuppert

Virtual Proxy - Show some code….

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@SvenRuppert

Virtual Proxy - Show some code….

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@SvenRuppert

Virtual Proxy - Show some code….

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@SvenRuppert

Virtual Proxy - Show some code….

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@SvenRuppert

Virtual Proxy - Show some code….

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@SvenRuppert

Interpreter - pre Java8

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@SvenRuppert

Interpreter - pre Java8

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@SvenRuppert

Interpreter - pre Java8

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@SvenRuppert

Interpreter - pre Java8

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@SvenRuppert

Interpreter - pre Java8

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@SvenRuppert

Interpreter - pre Java8

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@SvenRuppert

Interpreter - pre Java8

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@SvenRuppert

Interpreter - pre Java8

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@SvenRuppert

Interpreter - pre Java8

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@SvenRuppert

Interpreter - pre Java8

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@SvenRuppert

Interpreter - pre Java8

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@SvenRuppert

Interpreter - Java8 - Java9

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@SvenRuppert

Interpreter - Java8 - Java9

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@SvenRuppert

Interpreter - Java8 - Java9

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@SvenRuppert

Interpreter - Java8 - Java9

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@SvenRuppert

Main Idea - DataStructure to Function

Interpreter - Java8 - Java9

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@SvenRuppert

Main Idea - DataStructure to Function

Interpreter - Java8 - Java9

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@SvenRuppert

Main Idea - DataStructure to Function

Interpreter - Java8 - Java9

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@SvenRuppert

Interpreter - Java8 - Java9

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@SvenRuppert

Memoizing

pure functional behavior - show Source code

@SvenRuppert

@SvenRuppert

Memoizing @SvenRuppert

@SvenRuppert

Memoizing @SvenRuppert

@SvenRuppert

Memoizing @SvenRuppert

@SvenRuppert

Memoizing @SvenRuppert

@SvenRuppert

Memoizing @SvenRuppert

@SvenRuppert

Memoizing @SvenRuppert

@SvenRuppert

Memoizing @SvenRuppert

@SvenRuppert

Memoizing @SvenRuppert

@SvenRuppert

Memoizing @SvenRuppert

@SvenRuppert

Memoizing @SvenRuppert

@SvenRuppert

Memoizing @SvenRuppert

Reactive stuff

how use Functions… async…

@SvenRuppert

Observer

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@SvenRuppert

Observer

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@SvenRuppert

Observer

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@SvenRuppert

Observer

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@SvenRuppert

Observer

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@SvenRuppert

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@SvenRuppertJava8 - Concurrency - CompletableFuture

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@SvenRuppertJava8 - Concurrency - CompletableFuture

Process

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@SvenRuppertJava8 - Concurrency - CompletableFuture

Process

Thread

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@SvenRuppertJava8 - Concurrency - CompletableFuture

Process

Thread

Fiber

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@SvenRuppertJava8 - Concurrency - CompletableFuture

Process

Thread

Fiber

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@SvenRuppertJava8 - Concurrency - CompletableFuture

Process

Thread

Fiber

CompletionStage

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@SvenRuppertJava8 - Concurrency - CompletableFuture

Process

Thread

Fiber

CompletionStage

64

@SvenRuppertJava8 - Concurrency - CompletableFuture

Process

Thread

Fiber

CompletionStage

64

@SvenRuppertJava8 - Concurrency - CompletableFuture

Process

Thread

Fiber

CompletionStage CompletionStage

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@SvenRuppertJava8 - Concurrency - CompletableFuture

Process

Thread

Fiber

CompletionStage CompletionStage

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@SvenRuppertJava8 - Concurrency - CompletableFuture

Process

Thread

Fiber

CompletionStage CompletionStage CompletionStage

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@SvenRuppertJava8 - Concurrency - CompletableFuture

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@SvenRuppertJava8 - Concurrency - CompletableFuture

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@SvenRuppertJava8 - Concurrency - CompletableFuture

Value A

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@SvenRuppertJava8 - Concurrency - CompletableFuture

Value A Value B

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@SvenRuppertJava8 - Concurrency - CompletableFuture

Value A Value B

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@SvenRuppertJava8 - Concurrency - CompletableFuture

Value A Value B

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@SvenRuppertJava8 - Concurrency - CompletableFuture

Operator 1

Value A Value B

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@SvenRuppertJava8 - Concurrency - CompletableFuture

Operator 1

Value A Value B

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@SvenRuppertJava8 - Concurrency - CompletableFuture

Operator 1

Value A

Operator 2a

Value B

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@SvenRuppertJava8 - Concurrency - CompletableFuture

Operator 1

Value A

Operator 2a

Value B Value C

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@SvenRuppertJava8 - Concurrency - CompletableFuture

Operator 1

Value A

Operator 2a

Value B Value C

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@SvenRuppertJava8 - Concurrency - CompletableFuture

Operator 1

Value A

Operator 2a

Value B Value C

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@SvenRuppertJava8 - Concurrency - CompletableFuture

Operator 1

Value A

Operator 2a

Result

Value B Value C

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@SvenRuppertJava8 - Concurrency - CompletableFuture

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@SvenRuppertJava8 - Concurrency - CompletableFuture

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@SvenRuppertJava8 - Concurrency - CompletableFuture

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@SvenRuppertJava8 - Concurrency - CompletableFuture

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@SvenRuppertJava8 - Concurrency - CompletableFuture

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@SvenRuppertJava8 - Concurrency - CompletableFuture

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@SvenRuppertJava8 - Concurrency - CompletableFuture

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@SvenRuppertJava8 - Concurrency - CompletableFuture

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@SvenRuppertJava8 - Concurrency - CompletableFuture

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@SvenRuppertJava8 - Concurrency - CompletableFuture

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@SvenRuppertJava8 - Concurrency - CompletableFuture

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@SvenRuppertJava8 - Concurrency - CompletableFuture

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@SvenRuppertJava8 - Concurrency - CompletableFuture

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@SvenRuppertJava8 - Concurrency - CompletableFuture

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@SvenRuppertJava8 - Concurrency - CompletableFuture

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@SvenRuppertJava8 - Concurrency - CompletableFuture

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@SvenRuppertJava8 - Concurrency - CompletableFuture

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@SvenRuppertJava8 - Concurrency - CompletableFuture

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@SvenRuppertJava8 - Concurrency - CompletableFuture

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@SvenRuppertJava8 - Concurrency - CompletableFuture

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@SvenRuppertJava8 - Concurrency - CompletableFuture

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@SvenRuppertJava8 - Concurrency - CompletableFuture

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@SvenRuppertJava8 - Concurrency - CompletableFuture

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@SvenRuppertJava8 - Concurrency - CompletableFuture

Operator 1

Value A

Operator 2a

Result

Value B Value C

Java 9

some nice news…

@SvenRuppert

Java9 - Optional

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@SvenRuppert

Java9 - Optional

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@SvenRuppert

Java9 - Optional

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@SvenRuppert

Java9 - Optional

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@SvenRuppert

Java9 - Optional

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@SvenRuppert

Java9 - JEP266

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@SvenRuppert

Java9 - JEP266

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@SvenRuppert

we got Publisher / Subscriber

Java9 - JEP266

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@SvenRuppert

we got Publisher / Subscriber

Summary

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@SvenRuppert

places to read more about it

Summary

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@SvenRuppert

places to read more about it

www.functional-reactive.org

Summary

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@SvenRuppert

places to read more about it

www.functional-reactive.org

Summary

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@SvenRuppert

places to read more about it

www.functional-reactive.org

www.java-9.org

Summary

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@SvenRuppert

Now it is time to relax again ;-)

Summary

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@SvenRuppert

please, follow me ;-)

@SvenRuppert

Summary

81

@SvenRuppert

please, follow me ;-)

@SvenRuppert

Thank You !!!