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Quick look


SPRING BOOT                    

  • It is a way to ease to create stand-alone application with minimal or zero configurations.
  •  It is approach to develop spring based application with very less configuration. 
  • It provides defaults for code and annotation configuration to quick start new spring projects within no time. 
  • It leverages existing spring projects as well as Third party projects to develop production ready applications.
  •  It provides a set of Starter Pom’s or gradle build files which one can use to add required dependencies and also facilitate auto configuration.
  • – Spring Boot parent and starters make it much easier
  • Spring Boot works with Maven, Gradle, Ant/Ivy
  • – Embedded container is just one feature of Spring Boot
  •  Traditional WAR also benefits a lot from Spring Boot
  • – Automatic Spring MVC setup, including DispatcherServlet
  • – Sensible defaults based on the classpath content
  • – Embedded container can be used during development
  • Tomcat, Jetty, 

@Configuration
@ComponentScan
@EnableAutoConfiguration  = @SpringBootApplication


public class MyAppConfig {
public static void main(String[] args) {
SpringApplication.run(MyAppConfig.class, args);
}
}

 JAVA 8                         

 
STREAM
INTSTREAM
LONGSTREAM
DOUBLESTREAM
OF
Stream.Of(array)
Stream.of("str1","str2")
LIMIT OPERATION

Stream.Generate()
Stream.iterate()
DISTINCT OPERATION
(list/set).stream.distinct().foreach(x-'>'t;ysout(x);)
(list/set).stream.distinct().collect(toSet());
(list/set).stream.distinct().collect(toList());

CONCAT OPERATION 
Stream.concat(l1.stream(), l2.stream()).collect(Collectors.toList());

FOREACH OPERATION 
(list/set).stream.distinct().foreach()
COUNT OPERATION
(list/set).stream.count()
(list/set).stream.distinct().count()


MATCH OPERATION

(list/set).stream.(anyMatch()|allMatch()|noneMatch())
(list/set).stream.count()
(list/set).stream.distinct().count()
(list/set).stream.(anyMatch()|allMatch()|noneMatch())


FIND OPERATION

(list/set).stream.findAny()
(list/set).stream.findAll()
list.stream().filter(u -> u.getName().endsWith("sh"))
    .findFirst().orElse(null)


FILTER

(list/set).stream.filter(x->x%2).collect(toList()|toSet
list.stream().filter(u -> u.getName().endsWith("sh"))
    .findFirst().orElse(null);
list.stream().filter(u -> u.getName().endsWith("sh"))
    .forEach(u -> System.out.println(u.getName()));
FLATMAP


SORT

NATURAL ORDER :list.stream().sorted() 
REVERSE ORDER : list.stream().sorted(Comparator.reverseOrder()) 
BASED OF A PARTICULAR ATTRIBUTE
list.stream().sorted(Comparator.comparing(Student::getAge))
BASED OF A PARTICULAR ATTRIBUTE REVERSE ORDER


list.stream().sorted(Comparator.comparing(Student::getAge).reversed())
list.stream().max(Comparator.comparing(String::valueOf)).get();
list.stream().min(Comparator.comparing(String::valueOf)).get();
list.stream().sorted(Comparator.reverseOrder())









UI


    

  • JAVASCRIPT
    • 

  • JQUERY
    • 

  • REACT
    • 

  • ECHMA SCRIPT
    • 

  • ANGULAR JS
    • 

  • ANGULAR
    • 

  • FONTAWESOME
    • 

  • BOOTSTRAP
    

    • 

  • 1.   CONTAINER, CONTAINER-FLUID
2.   GRID DESIGN/RESPONSIVE DESIGN
3.   TYPOGRAPGHY
4.   NAVIGATION
    

    • 



    












MESSAGING

JMS

Purpose:Establish communication between two different systems




connectionFactory.createConnection();




connection.createSession(false, Session.AUTO_ACKNOWLEDGE);


connection.start();  
session.createConsumer((Destination) 


consumer.setMessageListener(msgHandler); 


session.createProducer((Destination) 



Connectionfactory








    

  • QueueConnectionFactory|TopicConnectionFactory
    • 

  • QueueConnection|TopicConnection
    • 

  • QueueSession|TopicSession
    • 

  • QueueSender|TopicPublisher
    • 

  • QueueReceiver|TopicSubscriber
    • 

  • Queue|Topic
    • 

  • MessageProducer: Produces messages to be send.
    • 

  • MessageConsumer :
    session.createConsumer((Destination)
    

    • 

  • Destination 
    
     
    • 

  • DurableConsumer
    MessageListener :TextListener|JSONListener
    • 

  • Session.AUTOACKNOWLEDGE
    • 


    • 




SPRING JMS


    

  • BASE CLASS :JMSACCESSOR,
    • 

  • 

CONNECTIONFACTORIES
    

    • 

  • 
AbstractConnectionFactory
    
AbstractRoutingConnectionFactory
    
CachingConnectionFactory
    

    • 

  • ActiveMQConnectionFactory 
    

    • 

  • 

MESSAGECONVERTER :
    

    
Strategy interface that specifies a converter between Java objects and JMS messages.
    

    • 

  • 
MappingJackson2MessageConverter, 
    

    
MarshallingMessageConverter, MessagingMessageConverter, SimpleMessageConverter
    

    • 

  • 
DESTINATION
    

    • 

  • JMSTEMPLATE
    • 

  • 

destination :
    

    • 

  • 

MESSAGECreator :
    

    • 

  •  variables, and functions.
    • 

  • 

MESSAGEselector
    

    • 

  • 

    
AbstractMessageProcessingSelector, AbstractXPathMessageSelector, BooleanTestXPathMessageSelector, 
    

    
ExpressionEvaluatingSelector
    

    

    • 

  • 

    

    • 







Message listener container, used for invoking messageReceiver.onMessage on message reception.





CACHE


    

  • GUAVA CACHE
    • 






 CacheBuilder.newBuilder()
         .maximumSize(100)                             
         .expireAfterAccess(30, TimeUnit.MINUTES).build(new CacheLoader(),personid)




    

  • EHCACHE
    • 

  • LRU
    • 

  • SPRING CACHE
    • 








SECURITY


    

  •    DATA INTEGRITY  : JCE
    • 

  •    AUTHENTICATION AND AUTHORIZATION : JAAS| SPRING SECURITY
    • 

  •    CONFIDENTIALITY : SSL/ NO -SSL/ 
    • 

  •    NON REPUDIATION : DIGITAL CERTIFICATES
    • 

  • OUTH2 
    • 






BATCH PROCESSING 




    

  •   SPRING BATCH
    • 










JOB SCHEDULING 


    

  •   QUARTZ 
    • 

  •    SPRINGQUARTZ
    • 








WEB SERVICES


    

  •  JAX-RS
    • 

  • JERSY 
    • 

  •  APACHE CXF 
    • 

  • SPRING REST
    • 

  • SPRING HATEOS
    • 

  • SPRING REST OUTH2 
    • 

  • AWS
    • 








MACHINE LEARNING 

MACHINE LEARNING                  


    

  • PYTHON
    • 





 Defining functions
2.     In bulit Functions
1.     print()
2.     str()
3.     len()
4.     slice()  slice_me[2:5]|sliceme[2:]
5.     integer//integer2
6.     input("",""),input()
7.     int()
8.     slice()  slice_me[2:5]|sliceme[2:]
9.      https://www.programiz.com/python-programming/methods/built-in
3.      Conditionals
1.       if(): elif:
2.      str()
 4.      Arrays
1.     num=['a','b','c','d']
2.     num.remove('c')
5.      Dictionary
       1. performances = {'Ventriloquism':'9:00am', 
    'Snake Charmer': '12:00pm'}
 2.      del performaces['Ventriloquism']
 6.      Looping
 1.       random.randint(1,53)
 2.      for items in menu_prices
 3.      for name,price in menu_prices.items()
 4.      for items in menu_prices
 5.      while guess != num:
 7.      Packages
             1.       random.randint(1,53)
 8.      Functions
              1.      def lotto_numbers():
              2.      
  9.      Reading/Writing Files
             1.      open()
             2.      file.write()
             3.      file.read()
  10.      Exceptions
             1.      open()
             2.      file.write()
             3.      file.read()  
  10.      Modules
             1.      open()
             2.      file.write()
             3.      file.read()




    

  • R  
    • 

  • R expressions, variables, and functions.
    • 

  • 

Vectors: Grouping values into vectors, then doing arithmetic and graphs with them.
    
Matrices :Creating and graphing two-dimensional data sets.
    
Summary Statistics :Calculating and plotting some basic statistics: mean, median, and standard deviation.
    
Factors :Creating and plotting categorized data.
    
Data Frames :Organizing values into data frames, loading frames from files and merging them.
    
Real-World Data :Testing for correlation between data sets, linear models, and extending R with additional libraries    .
    

    • 








DATA                             


    

  •  JAXB :JAXBCONTEXT,MARSHALLER,UNMARSHALLER,JAXBEXCEPTION.
    • 


    • 

  •  JACKSON
    • 

  • OBJECTMAPPER.READVALUE(),WRITEVALUE
    • 

  • JSONFACTORY,JSONGENERATOR
    • 

  • 
JsonGenerator generator = factory.createGenerator(
    

    
new File("data/output.json"), JsonEncoding.UTF8)
    

    
;
    

    • 

  • JSONFACTORY,JSONPARSER,JSONTOKEN 
    • 

  • 
JsonFactory factory = new JsonFactory();
    

    • 

  • 
JsonParser  parser  = factory.createParser(carJson);
    

    • 

  • 

    

    • 

  •  SPRING OXM
    • 

  • MARSHALLER|STREAMSOURCE
    

    • 

  • UNMARSHALLER|STREAMRESULT
    

    • 

  • CASTORMARSHALLER
    

    • 

  • 

    

     @Bean
 public CastorMarshaller getCastorMarshaller() {
   CastorMarshaller castorMarshaller = new CastorMarshaller();
   Resource resource = new ClassPathResource("mapping.xml");
   castorMarshaller.setMappingLocation(resource);
   return castorMarshaller;
 }
    

    

    

    

    • 

  • 

    

    

    

    MARSHALLING
fis = new FileInputStream(fileName);
            return unmarshaller.unmarshal(new StreamSource(fis));
UNMARSHALLING
fos = new FileOutputStream(fileName);
marshaller.marshal(graph, new StreamResult(fos))
    

    

    

    

    

    • 






PERSISTENCE 




    

  • JDBC
    • 

  • SPRING JDBC
    • 

  • org.springframework.jdbc.core.JdbcTemplate 
    • 

  • return jdbcTemplate.update(query): will take insert|update|delete query
    • 

  •  return jdbcTemplate.execute(query,new PreparedStatementCallback()
    • 

  • return template.query("select * from employee",new ResultSetExtractor>(){  
    

    • 

  • NamedParameterJdbcTemplate :Creating and plotting categorized data
    • 

  • SimpleJdbcTemplate
    PreparedStatement using given arguments. :Creating and graphing two-dimensional data sets.
    • 

  • public List query(String sql, RowMapper rse)
    ResultSetExtractor 
    • 

  • DataAccessException
    • 



UNIT TESTING: MOCKITO             

TO DOS 2018: GO_OVER MOCKITO,EASYMOCK,JMOCKIT,POWERMOCK


    

  • JUNIT4
    • 

  • BDDMOCKITO
    • 

  • MOCKITO
    • 

  • WHEN.THEN INTERACTION 
    • 

  • VERIFY 
    • 

  • @Mock, @Spy, @Captor and @InjectMocks
    • 







    

  • Mockito.spy() – to spy on a real object.
    • 




List spyList = Mockito.spy(list)



OR @Spy



List spyList = new ArrayList();



Stubbing a spy



Mockito.doReturn(100).when(spyList).size();



assertEquals(100, spyList.size());



mock vs spy










@Test
public void whenCreateMock_thenCreated() {
    List mockedList = Mockito.mock(ArrayList.class); 
    mockedList.add("one"); // It mocked ,didnt actually add
    Mockito.verify(mockedList).add("one"); 
    assertEquals(0, mockedList.size());
}
@Test
public void whenCreateSpy_thenCreate() {
    List spyList = Mockito.spy(new ArrayList()); 
    spyList.add("one");  // It actually add
    Mockito.verify(spyList).add("one"); 
    assertEquals(1, spyList.size());
}










MyList listMock = Mockito.mock(MyList.class);









WHEN ..THEN




    

  • when(listMock.add("aaa")).thenReturn(false); 
    • 

  • doReturn(false).when(listMock).add("aaa"; 
    • 




ASSERTIONS




    

  • boolean added = listMock.add(randomAlphabetic(6));
    • 

  • assertThat(added, is(false));
    • 

  • assertThat(listMock.size(), equalTo(1))
    • 

  • assertThat(element, is(equalTo("Always the same")));
    • 

  • assertEquals(100, spyList.size());
    • 











THROW EXCEPTIONS


    

  • when(listMock.add("aaa")).theThrow(IllegalStateException.class)
    • 

  • doThrow(NPE.class).when()
    • 







MULTIPLE CALLS


when(listMock.add("aaa"))
  .thenReturn(false)
  .thenThrow(IllegalStateException.class); 


 CALL REAL METHOD














 SPY










MyList instance = new MyList();
MyList spy = Mockito.spy(instance); 
doThrow(NullPointerException.class).when(spy).size();
spy.size(); // will throw the exception




CUSTOM ANSWER






doAnswer(invocation -> "Always the same").when(listMock).get(anyInt()); 










VERIFY : IS JUST TO VERFIY THAT YOU DID TEST ACTION 


; IT GOT EXECUTED










List mockedList = mock(MyList.class);





verify(mockedList).size();



verify(mockedList, times(1)).size();


verifyZeroInteractions(mockedList);


verify(mockedList, times(0)).size();



verifyNoMoreInteractions(mockedList);



verify order of interactions
List mockedList = mock(MyList.class);
mockedList.size();
mockedList.add("a parameter");
mockedList.clear(); 
InOrder inOrder = Mockito.inOrder(mockedList);
inOrder.verify(mockedList).size();
inOrder.verify(mockedList).add("a parameter");
inOrder.verify(mockedList).clear();


verify(mockedList, never()).clear(); 




verify(mockedList, atLeast(1)).clear();
verify(mockedList, atMost(10)).clear();
verify interaction with exact argument
verify(mockedList).add("test");


mockedList.add("test");


verify(mockedList).add("test");//verify interaction with flexible/any argument



verify interaction using argument capture
List mockedList = mock(MyList.class);
mockedList.addAll(Lists. newArrayList("someElement"));
ArgumentCaptor argumentCaptor = ArgumentCaptor.forClass(List.class);
verify(mockedList).addAll(argumentCaptor.capture());


Mockito.verify(mockedList).add(argCaptor.capture());
List capturedArgument = argumentCaptor.> getValue();
assertThat(capturedArgument, hasItem("someElement"));













MOCKITO ANNOTATIONS





Configure



@RunsWith(MockitoJUnitRunner.class)//Mockito

@RunWith(EasyMockRunner.class)// EasyMock

@RunWith(JMockit.class)

or 

@Before

public void init(){

MockitoAnnotations.initMocks(this);

}











____________________________________________________



WITH ANNOTATIONS



@Mock





List mockedList;

-----------------------------------------------------

WITHOUT ANNOTATIONS



ListMockito.mock



(List.class);



____________________________________________________

WITH ANNOTATIONS



@Spy

List spyList;

-----------------------------------------------------

WITHOUT ANNOTATIONS





ListMockito.spy

(List.class);____________________________________________________

WITH ANNOTATIONS



@Captor

ArgumentCaptor argCaptor;



Mockito.verify(mockedList).add(argCaptor.capture());

-----------------------------------------------------

WITHOUT ANNOTATIONS



 ArgumentCaptor arg = ArgumentCaptor.forClass(String.class);



mockList.add("one");





Mockito.verify(mockList).add(arg.capture());



____________________________________________________



WITH ANNOTATIONS







@InjectMocks





MyDictionary dic = new MyDictionary();



assertEquals("aMeaning", dic.getMeaning("aWord"));

____________________________________________________                  

RULES









    @Rule



    public VerificationCollector verificationCollector = MockitoJUnit.collector();





Spring









@ActiveProfiles("test")



@RunWith(SpringJUnit4ClassRunner.class)





@SpringApplicationConfiguration(classes = MocksApplication.class)



EASYMOCK

@RunWith(EasyMockRunner.class)

EasyMock.replay(loginService);

EasyMock.verify(loginService);

EasyMock.expect(userForm.getUsername()).andReturn("foo");

EasyMock.expect(loginService.login(userForm)).andReturn(true);



    loginService.setCurrentUser("foo");



EasyMock.replay(userForm);



EasyMock.replay(loginService);



Assert.assertEquals("OK", login);



EasyMock.verify(userForm);



EasyMock.verify(loginService);






LINUX                             




    

  • JSCH
    • 

  • JSFTP
    • 

  • LINUX COMMANDS
    • 






* * * * *  command to execute
│ │ │ │ │
│ │ │ │ └─── day of week (0 - 6) (0 to 6 are Sunday to Saturday, or use names; 7 is Sunday, the same as 0)
│ │ │ └──────── month (1 - 12)
│ │ └───────────── day of month (1 - 31)
│ └────────────────── hour (0 - 23)
└─────────────────────── min (0 - 59)







DATA STRUCTURES















ALGORITHMS


    

  • SEARCH 
    • 

  • SORTING 
    • 

  • SEQUENCE 
    • 




COLLECTION



Interface Implemented




    

  • RANDOM ACCESS TO TAKE SAME TIME TO ACCESS ELEMENTS
    • 

  • SERIALIZATION
    • 

  • CLONING INTERFACE
    • 






CONCURRENCY                      


    

  • BLOCKING QUEUE
    • 

  • ARRAY BQ
    • 

  • BLOCKING QUEUE : DS TO HOLD THREAD OBLECTS
    • 

  • ARRAY BQ : 
    • 

  • LINKED BQ:
    • 

  • SYNCHRNOUS BQ:
    • 

  • CYCLIC BARRIER: 
    • 

  • SEMAPHORE :
    • 

  • RENTRANT LOCK
    • 

  • FORK AND JOIN CALL 
    • 

  • PRODUCER CONSUMER
    • 

  • ATOMIC BOOLEAN 
    • 

  • ATOMIC INTEGER
    • 

  • ATOMIC LONG 
    • 

  • ATOMIC REFERENCE
    • 

  • READ WRITE LOCK
    • 

  • EXCHANGER : COMMUNICATION BETWEEN THREADS
    • 

  • COUNTDOWNLATCH:
    • 

  • CONCURRENTLINKEDQUEUE
    • 

  • DELAY BQ
    • 














FILE HANDLING                     




MAVEN                             



Archetype is a plugin that creates project structure



mvn archetype:generate 


-DgroupId = com.companyname.automobile 
-DartifactId = trucks
-DarchetypeArtifactId = maven-archetype-webapp 
-DinteractiveMode = false


    

  • GROUP ID
    • 

  • ARTIFACT ID
    • 

  • DEPENDENCIES
    • 

  • PLUGINS
    • 

  • 
GOALS
    

    • 

  • PREPARE-RESOURCES|VALIDATE|COMPILE|PACKAGE|INSTALL|DEPLOY
    • 

  • PRINT DATA ON CONSOLE|maven-antrun-plugin
    • 

  • CREATE JAR|maven-jar-plugin
    • 

  • CREATE WAR|maven-war-plugin
    • 

  • CREATE EAR| maven-ear-plugin
    • 

  • CREATE RAR|maven-rar-plugin
    • 

  • COMPILE CODE|maven-compiler-plugin
    • 

  • UNIT TESTING CODE||maven-surefire-plugin
    • 

  • CREATE PROJECT DOCUMENTATION
    • 

  • CREATE PROJECT REPORTS
    • 

  • INSTALL| maven-install-plugin
    • 

  • CREATE JAVADOC|maven-javadoc-plugin
    • 

  • JUNIT TEST CASES
    • 


    • 



















































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