2023-06-06 09:15
Abstract
methods are defined using {abstract} modifier. This modifier can be used at
start or end of the line.
abstractMethod.[email protected]
abstract class ArithmeticUtil{
int sum(i… Read More
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Tutorial on Java, Design Patterns, collections, Struts, jdbc
2023-06-06 09:08
‘data-testid’
attribute is used to identify a DOM node for testing purposes. 'page.getByTestId()'
method Locate element by the test id. By default, the 'data-testid' attribute
is… Read More
2023-06-06 08:52
@PostConstruct
annotation is applied on a method that needs to be executed after dependency
injection is done to perform any initialization. This method must be invoked before the clas… Read More
2023-06-05 11:46
/ is a division operator, whereas // is a floor
division operator. Python division (/) operator return the result of division
in floating point number, whereas floor division operator (//) r… Read More
2023-06-05 08:56
Below
table summarizes the visibility levels supported by PlantUML.
Symbol
Description
-
private
#
protected
~
package
priv… Read More
2023-06-05 08:51
page.getByTitle()
method locate the elements that match to given title.
SignatureLocator getByTitle(String text)
Locator getByTitle(String text, GetByTitleOptions options)
Locator g… Read More
2023-06-05 08:46
By
listening on 'ServerStartupEvent', we can execute the code when the server
completes startup.
[email protected]
public class AppEventListeners {
@Inject
EmbeddedServer e… Read More
2023-06-04 07:40
Micronaut
application runs on the port 8080 by default. You can customize this to a
specific port with below configuration.micronaut:
server:
port: 8888
Find t… Read More
2023-06-04 07:39
Use the
following application configuration to run the Micronaut application on a
random port.micronaut:
server:
port: -1
Find the
below working application… Read More
2023-06-04 07:32
page.getByPlaceholder()
method return the locate the input elements by the placeholder text.
SignatureLocator getByPlaceholder(String text)
Locator getByPlaceholder(String text, Get… Read More
2023-06-04 07:31
You can
use page.getByAltText method to locate the elements by their alt text.
ExampleElementHandle elementHandle = page.getByAltText("plantuml").elementHandle();… Read More
2023-06-04 07:24
Using the
arrow (), we can clearly specify which object act on other object.
ExamplePerson --> Address : lives at >
Car --> Person :
labelArrow.txt… Read More
2023-06-04 07:24
Using the
symbol : followed by the field’s or method’s name we can define methods,
fields.
defineFieldsMethods.tx[email protected]
class Object
Object : Object clone()
Object… Read More
2023-06-02 14:57
Using 'page.getByLabel()'
method, we can interact with an element using label text.
For
example, we can use this method to fill the text field data, to locate a radio
button by asso… Read More
2023-06-02 14:51
To model many
to many relationship, you can use double-quotes "" on each side of
the relation.
ExampleStudent "0..*" -- "1..*" Course
manyToMany.txt
@st… Read More
2023-06-01 11:40
To model
one to many relationship, you can use double-quotes "" on each side
of the relation.
ExampleHuman "1" -- "many" BodyParts
Human "1" -- "1..*" BodyParts
Ab… Read More
2023-06-01 11:37
Using
page.getByText() method, we can locate the elements by text content.
SignatureLocator getByText(String text)
Locator getByText(String text, GetByTextOptions options)
Locator g… Read More
2023-06-01 11:31
This is
continution to my previous post. In this post, I am going to explain how to
test the rest api.
API
details are given below:
url:
/welcome
method:
GET
expectedMessag… Read More
2023-05-30 13:56
Using python built-in function ‘len()’, we can get the
number of characters in a string.
no_of_chars_in_string.pystr = 'Hello World'
msg = f'"{str}" has {len(str)} chara… Read More
2023-05-30 13:55
Using string.replace() method, we can replace all the
matching substrings in a string.
replace_sub_string.pystr1 = 'hello there, hi there'
str2 = str1.replace('there', 'Krishna')… Read More
2023-05-30 09:00
Formatted strings in Python provide a way to evaluate
the expressions in a String. Formatted strings are defined with prefix 'f',
followed by a string that contain some placeholders to repla… Read More
2023-05-30 06:00
Simple
controller snippet in Micronaut looks like [email protected]("/welcome")
public class WelcomeController {
@Get(produces = MediaType.TEXT_PLAIN)
public String index() {
return "We… Read More
2023-05-30 06:00
Previous … Read More
2023-05-30 05:40
'page.getByRole()'
method locate the elements by their ARIA role.
SignatureLocator getByRole(AriaRole role)
Locator getByRole(AriaRole role, GetByRoleOptions options)
… Read More
2023-05-30 04:29
We can add
label on a relation using : followed by a label text.
ExampleHuman *-- Brain : contains
addLabel.txt
@startuml
title "Class Composition"
cl… Read More
2023-05-29 11:33
Boolean variable can hold either True or False, and
the type ‘bool’ represents a Boolean type.
Exampleis_raining = True
is_raining = False
Please note… Read More
2023-05-29 11:32
Using bool() method, we can convert a string to
boolean in Python.
Examplebool_val = bool(input_str)
string_to_boolean.py
input_str = input('Enter a string '… Read More
2023-05-29 10:57
Using float() function, you can convert a string to a
float in Python.
Examplefloat_var = float(input_str)
float_to_int.py
input_str = input('Enter a st… Read More
2023-05-29 10:57
Using int() function, you can convert a string to an
integer in Python.
Exampleint_var = int(input_str)
string_to_int.py
input_str = input('Enter a stri… Read More
2023-05-29 06:55
In my
previous post, we learned about below symbols.
: Extension
*-- : Composition
o-- : Aggregation
Apart from
those, fo… Read More
2023-05-29 06:51
Locators
are used to find the elements in a page.
Below
table summarize are the recommended
locators.
Locator
Description
page.getByRole()
L… Read More
2023-05-26 11:43
Locator.uncheck()
method uncheck the radio button or checkbox.
Signature
void
uncheck()
void
uncheck(UncheckOptions options)
Example
page.getByLabel("java").uncheck();… Read More
2023-05-26 11:37
Using ..
(dots), we can use dotted lines to connect entities in class diagram.
[email protected]
title "Class Composition"
class Human
Class Brain
class Lungs
class Liver
c… Read More
2023-05-26 11:12
A method Adapter
advice applicable to a method that will create an entirely new bean definition
that delegates to the annotated method.
For
example the following snippet runs the lo… Read More
2023-05-25 15:06
In this
post, I am going to demo an utility class to print the table data in left
aligned, right aligned, left aligned in upper case and right aligned in upper
case etc.,
I am using… Read More
2023-05-24 11:03
Multiset
is similar to a Set, but it allows duplicate elements. Repetition of the
elements in Multiset is explicitly counted.
For
example,
a.
The
set {1, 2} con… Read More
2023-05-24 05:34
Introduction
advice introduces new behavior to a class.
Step 1: Define
Introduction [email protected]
@Bean
@Documented
@Retention(RUNTIME)
@Target({ TYPE, ANNOTATION_TYPE, METH… Read More
2023-05-24 05:22
Aggregation
is specified using the symbol o--
[email protected]
title "Class Aggregation"
class Car
Class Engine
class Transmission
class Battery
class Alternator
cla… Read More
2023-05-24 05:18
Using
Locator.setChecked() method, we can check or uncheck the checkbox.
Signaturevoid setChecked(boolean checked)
void setChecked(boolean checked, SetCheckedOptions options)… Read More
2023-05-23 05:18
Aspects
are used to implement the cross cutting concerns like logging, transaction
management etc.,
Application
code is separated from cross cutting concerns in the form of aspects… Read More
2023-05-23 05:17
In this
post, I am going to show how to decorate a method using @Around advice.
Step 1: Define
@Around [email protected]
@Retention(RUNTIME)
@Target({ TYPE, METHOD })
@Around
publi… Read More
2023-05-23 04:55
Locator.selectText()
method select all the text content attached to element mapped to this selector.
Signaturevoid selectText()
void selectText(SelectTextOptions options)
… Read More
2023-05-23 04:42
Class
composition is defined using the symbol *--
[email protected]
title "Class Composition"
class Human
Class Brain
class Lungs
class Liver
class Heart
class Stomac… Read More
2023-05-22 12:13
FNV hash algorithms
are designed to be fast while maintaining a low collision rate. The primary
objective of FNV hashes is to achieve fast performance while minimizi… Read More
2023-05-22 10:28
Define an
utility class to work with the following features.
1.
Get
all the primitive types
2.
Get
all the wrapper types
3.
Ch… Read More
2023-05-22 06:32
We can
specify class extension using the symbol
[email protected]
title "Class Inheritance or extension"
abstract class Mammal
Class Dog
class BullDog
class Poodle
cla… Read More
2023-05-22 06:29
Locator.page()
method return the page reference from the locator.
SignaturePage page()
Example
String pageTitle = firstMatchingElement.page().title();… Read More
2023-05-20 15:01
Locator.nth()
method returns locator to the n-th matching element. Index is 0-based.
SignatureLocator nth(int index)
Example
Locator secondMatchingEleme… Read More
2023-05-20 14:53
Class
diagrams are the core building blocks in object-oriented modelling and
represent the static view of a system.
Following
snippet describes different elements provided by PlantU… Read More
2023-05-20 14:49
We can
define an immutable configuration by defining a class and use the
@ConfigurationInject annotation on a constructor of a @ConfigurationProperties
or @EachProperty bean.
Exampl… Read More
2023-05-19 15:03
Example1: Metric to capture api’s response time
Following
metrics to be captured on api response time.
a.
Total
number of requests
b.
Sum
of all the… Read More
2023-05-19 14:54
@JsonCreator
annotation can be applied on constructor and factory methods and used for instantiating new instances of the
associated class.
Every
argument of @JsonCreator anno… Read More
2023-05-19 14:53
@JacksonInject
annotation specifies that the value of annotated property will be injected
during deserialization. We can use this feature, if we want to add additional
information which is n… Read More
2023-05-19 13:27
Jackson
uses the field names as keys and the field value as the value during
serialization. However, using the @JsonValue annotation we can customize the
serialization process by specifying… Read More
2023-05-18 14:59
There are
two ways to define immutable configuration.
a.
Using @ConfigurationProperties annotation on an interface.
b.
Using
the @ConfigurationInject annotation on… Read More
2023-05-18 14:58
In this
post, let’s learn how to define an immutable configuration using @ConfigurationProperties
annotation.
How to
define an immutable configuration?
Just define an interfa… Read More
2023-05-18 14:50
We can customize
the color or style of elements using the below inline style.
#[color|back:color];line:color;line.[bold|dashed|dotted];text:color
objInlineStyl… Read More
2023-05-18 14:45
Locator.last()
method return the locator of last matching element.
SignatureLocator last()
Example
Locator lastMatchingElement = page.locator(".para").l… Read More
2023-05-18 14:16
Below
snippet get the map from employees array, where key is the employee id and
object is employee itself.Map empById = unmodifiableMap(Arrays.stream(emps).collect(Collectors.toMap(Employee… Read More
2023-05-18 14:09
In this
post, I am going to explain how to get a Map from an enum.private static enum Month {
JANUARY(1),
FEBRUARY(2),
MARCH(3),
APRIL(4),
MAY(5),
JUNE(6)… Read More
2023-05-18 14:00
In this
post, I am going to explain about an utility class that provide below
functionalities with respect to a field.
a.
Check
whether a field has getter and setter met… Read More
2023-05-17 13:09
Java bean
is a class that is adhere to following conventions.
a. Private fields with corresponding getter and setter methods.
b.
Class
must have a public no-argument con… Read More
2023-05-17 06:47
@EachBean
allows to define beans from the presence of other bean definitions. In general,
it is used in conjunciton with @EachProperty annotation.
For example,@EachProperty(value =… Read More
2023-05-17 06:25
There are
multiple ways to check whether an element is visible or not in a page.
Approach
1: Using
page.locator(someLocator).isVisible() method
isVisible()
method return true, if… Read More
2023-05-17 05:01
We can customize
the color or style of arrows using the below inline notation.#color;line.[bold|dashed|dotted];text:color
customizeArrowColor.txt
@startuml
acto… Read More
2023-05-16 04:43
Just add /
after the actor to draw a Business actor.
[email protected]
:actor1:/
:actor2:/ as act2
actor/ actor3
actor/ :actor4: as act4
@enduml
A… Read More
2023-05-16 04:39
Locator.isHidden
method return true when the element is hidden, else false.
Signatureboolean isHidden()
boolean isHidden(IsHiddenOptions options)
Example… Read More
2023-05-16 04:34
This is
continuation to my previous post. In my previous post, I explained how to
derive beans using @EachProperty annotation from a map style of configuration.
But there are situations, whe… Read More
2023-05-15 04:57
Let me
explain it with below sample configuration.app:
datasource:
devSource:
connection-timeout: 3000
max-lifetime: 4000
maximum-pool-size: 5
qaSource:… Read More
2023-05-15 04:43
Locator.isEnabled()
method return true, when the element is enabled, else false.
Signatureboolean isEnabled()
boolean isEnabled(IsEnabledOptions options)
Fi… Read More
2023-05-15 04:36
Just add /
to draw a Business Use Case.
[email protected]
(business use case 1)/
(business use case 2)/ as (UC2)
usecase/ "business use case 3"
usecase/ (business use ca… Read More
2023-05-13 13:07
[email protected]
left to right direction
skinparam packageStyle rectangle
actor customer as C1
rectangle checkout {
C1 -- (checkout)
(checkout) -> (payment) : pay the mone… Read More
2023-05-13 13:03
Locator.isEditable()
method return true when the element is editable, else false.
Signatureboolean isEditable()
boolean isEditable(IsEditableOptions options)
Exam… Read More
2023-05-13 12:57
In this
post, let’s see how can we define custom type converters in Micronaut.
Let’s
define a custom type converter, that read the employee details in csv format
and map… Read More
2023-05-12 07:19
MapFormat
annotation bind the properties to a map. You can apply either of following
transformations to the MapFormat annotation.
a.
NESTED:
A nested map has the any key… Read More
2023-05-12 07:08
Locator.isDisabled()
method return true, if the selected element is disabled, else false.
Signatureboolean isDisabled()
boolean isDisabled(IsDisabledOptions options)… Read More
2023-05-12 06:28
using
skinparam
Using
skinparam, we can customize font and colors.
[email protected]
left to right direction
skinparam usecase {
BackgroundColor DarkSeaGreen
BackgroundCol… Read More
2023-05-11 02:26
Use case
diagram direction is top to bottom by default, we can customize this to ‘left
to right’ with below statement.
Syntaxleft to right direction
to… Read More
2023-05-11 02:22
Locator.inputValue()
(or) page.inputValue() method return the input.value for the selected
, or element.
SignatureString inputValue()
String inputValue(InputValueOptions options)… Read More
2023-05-11 02:14
The @Format
annotation can be used on setters to specify the date format to use when
binding java.time date objects.
application.yml my:
app:
publishedDate: 2021-11-14… Read More
2023-05-09 12:50
Below
snippet return an enumeration from the iterator in Java.private static Enumerationenumeration(Iterator iterator) {
return new Enumeration() {
public boolean hasMoreElements() {… Read More
2023-05-09 12:35
Using
Collections.enumeration method, we can get an enumeration over the specified
collection.
Signaturepublic static Enumerationenumeration(final Collection c)
Ex… Read More
2023-05-09 12:22
HashTable
HashTable
is a data structure that maps keys to values. Any non-null object can be used
as a key or as a value.
HashTable
vs HashMap
HashMap is
almost equivalent to Hash… Read More
2023-05-09 08:44
In this
post, I am going to explain about an utility class to made your work easier
while working with reflections.
Utility
class provide below methods.
a.
Get
an insta… Read More
2023-05-09 04:33
@ReadableBytes
annotation can be used to process the strings in the form of kb, gb, mb etc.,
Following
table summarizes how the readable bytes conversion is happening.
C… Read More
2023-05-09 04:19
Locator.innerText()
return the value of 'element.innerText' associated with the given element.
SignatureString innerText()
String innerText(InnerTextOptions options)… Read More
2023-05-09 04:13
Using
newpage keyword, we can split the diagram into multiple pages.
[email protected]
actor user1
actor user2
usecase "use case 1" as UC1
usecase "use case 2" as U… Read More
2023-05-08 16:25
Implement
an utility class such that, it takes a code snippet and executes with the
configured number of retries until it is successful.
Find the
below working application.
… Read More
2023-05-08 11:06
Spliterator
instance is used to traverse and partition the elements of a source. Array,
Collection, IOChannel etc., come under spliterator source.
Example
1: Traverse the List
eleme… Read More
2023-05-08 09:15
Use ..>
to put a dotted arrow between the objects in use case diagram.
[email protected]
actor user
usecase "use case 1" as UC1
usecase "use cas… Read More
2023-05-08 09:10
Locator.innerHTML()
method return element.innerHTML value.
SignatureString innerHTML()
String innerHTML(InnerHTMLOptions options)
Example
String innerH… Read More
2023-05-08 09:00
You can
specify the lists and arrays in application property file and read them as a
list.
Step 1: Define the collection of values in
application.yml file.my:
app:
primes:… Read More
2023-05-03 14:16
In this
post, I am going to explain how to get the Stream from an Enumeration in Java.
Step 1:
Get an instance of Spliterator
from Enumeration.
Spliterator spliterator = new Splite… Read More
2023-05-03 13:50
Using
StreamSupport# stream
method, we can get a new sequential or parallel Stream.
Step 1:
Get the spliterator
from iterator.
'Spliterators.spliterator'
method return a s… Read More
2023-05-03 10:27
Below
snippet join the collection elements by a delimiter using streams.public static String join(final Collection> collection, final String delimiter) {
if (collection == null) {
retu… Read More
2023-05-03 10:05
Write a method
such that it takes a string and prefix as arguments and remove the prefix from
given string.
Signaturepublic static String removePrefix(final String inputStr, final S… Read More
2023-05-03 09:19
Write a function
that converts the human readable memory representation to a long value in
bytes. Please find the below table for the inputs and outputs.
Input
Output
(… Read More
2023-05-03 09:18
Write a method
such that it takes a string and suffix as argument and remove the suffix from
given string.
Signaturepublic static String removeSuffix(final String inputStr, final St… Read More
2023-05-03 08:48
Following snippet converts
the exception or a throwable stack trace to string representation.public static String throwableToString(Throwable t) {
try (StringWriter stringWriter = new Stri… Read More
2023-05-03 07:00
Write a
method that takes a string and a character as arguments, and split the string
by given character using String indexOf method.
Signaturepublic static Listsplit(String data, i… Read More
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