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What is MVC?

MVC standards for Model-View-Control. It is an architectural pattern that splits the application into three major components.

1. Model deals with business logic and database interactions

2. Controller coordinates the activities between the model and the view

3. View is responsible for data presentation

Loose coupling -the components exist and function independently of each other.

Flexibility – one can easily make changes to individual components

Increased productivity – more than one person can work on the project at the same time. The front-end developers can work on views and presentation while backend developers can focus on models and since the system is loosely coupled, it works at the end of the day

In this tutorial, you will learn:

Model

The model is responsible for interacting with data sources. This is usually a database, but it can also be a service that provides the requested data. It is also a common practice to have the business logic contained in the models as opposed to the controller. This practice is usually termed fat model skinny controller.

The model usually writes data into the database, provides a mechanism for editing and updating, and deleting data. In a modern web application, models use data access design patterns such as active record to make interacting with the database easier.

For example, CodeIgniter uses a built-in library Active Record to aid the models while other frameworks such as Laravel use Eloquent Object Relational Mapper (ORM) that aids data access.

Controller

The controller listens for incoming requests for resources from the users. It acts as the intermediate between the model and the view and at times implements some business rules as well. Let’s say the controller receives a request to register a user in the database.

The controller may perform data validation on what has been submitted to ensure that all the required parameters have been submitted. If something is missing the user is redirected to the registration page with the appropriate error message displayed. The controller may also request the model to perform more validation by checking if the submitted email address already exists. If all validation rules pass then the controller submits the data to the model for process and waits for the response.

View

The view deals with data presented to the end user. In web applications, views often contain HTML, CSS, and optionally JavaScript. Views contain minimum programming code. The code contained in views is usually used to loop through collections of data received as parameters from the model or helper function for cleaning up data or creating links to edit the records. Most modern web application usually uses templating engines that define their own syntax which is more like pseudocode and can easily be understood by designers. When working with CodeIgniter, it is common practice to use short PHP tags and control structures. To display something in CodeIgniter, one might use the following code

As opposed to

<?php echo $title;

Control structures are usually written as follows

As you can see from the above example, the view will use a combination of PHP and HTML instead of enclosing everything in pure PHP code.

How MVC frameworks work?

The following image shows the MVC framework works

A controller receives the request from the user, interacts with the database model if necessary then returns the result back to the browser in the form of HTML code which the browser interpreted into a human-readable format and displayed to the user.

CodeIgniter Controller

Let’s now breakdown what just happened when we loaded the above URL into the web browser.

Open the file chúng tôi controller located application/controllers

You should be able to see the following code

<?php defined('BASEPATH') OR exit('No direct script access allowed'); class Welcome extends CI_Controller { public function index() { } }

HERE,

defined(‘BASEPATH’) OR exit(‘No direct script access allowed’); prevents direct access to the controller if the request didn’t come through chúng tôi this is for security purposes.

class Welcome extends CI_Controller {…} defines the Welcome controller class and extends the parent class CI_Controller

We will now update the index method as follows

public function index() { }

HERE,

CodeIgniter Model

Let’s now create the view that we referenced in the above code. For simplicity’s, our model will not interact with the database but will return a static customer record. We will work with databases in the next tutorials.

Create a file Customers_model.php in application/models

Add the following code

<?php class Customers_model extends CI_Model { public function get_customer($id) { $data['id'] = 3; $data['first_name'] = 'John'; $data['last_name'] = 'Doe'; $data['address'] = 'Kingstone'; return $data; } }

HERE,

class Customers_model extends CI_Model {…} defines the model Customers_model that extends CI_Model.

public function get_customer($id) {…} defines the get customer method based on a customer id

$data[…] defines the static values of our fictious customer. This should be a row returned from the database.

return $data; returns the customer data.

That is, it for our model. Let’s now modify the welcome_message view

Open welcome_message.php located in

application/views/welcome_message.php

Replace the code with the following

Save the changes

Load the following URL in the web browser

You should be able to see the customer card as shown in the image below

Summary

MVC is an architectural pattern that splits the application into three major components

The model is responsible for interacting with data sources

The controller listens for incoming requests for resources from the users

In web applications, views often contain HTML, CSS, and optionally JavaScript

A controller receives the request from the user, interacts with the database model if necessary then returns the result back to the browser in the form of HTML code

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How Does Angelscript Work With Example

Introduction of AngelScript

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Why do we Need AngelScript?

AngelScript is needful because it is a powerful object-oriented scripting language like c/c++. It has an extremely flexible cross-platform scripting library; hence the scripts or a computer program written can work on any platform, and the scripting library is designed to improve the functionality of the script; by using it, users can extend the functionality with the help of external scripts.

It also has a feature that we can call the c and c++ functions within the angel-script environment; due to that, it is helpful to the developers to work with it, and the syntax of the angel-script class was closely followed by the syntax in c++ classes. So that it is needful for developers who are worked with c++ and they have to work on angel-script, then they can work easily.

Angelscript can be used in robotics that means the behavior rules of robotic are followed by angel-script. Also, it is useful for video game development, which increases the life of a game. So by using angle-script, get the project up, and that will run faster. And by using an external script, we can improve the functionality of the application.

How does AngelScript Work?

First, we need the application of angel-script and then have to register the interface so that script can interact with the application; the interface contains functions, variables, and classes also.

Secondly, we have to set message call back to receive information about errors, errors in human-readable form, because if the registration is not done correctly, then attention message will get as a callback message about the incorrect registration or a script has an error that fails to compile. If we need to verify the return code, there is no need to take much effort to know it because the call-back message can give information in the human-readable form so that we can correct it. These two steps are about engine configuration.

After engine configuration next step is to compile the script that should be executed. Also, need to write a function to call the registered print function and will give the output that function is stored in files.

In this step, has to write code for loading script files and to compile it, there is a CSriptbuilder define it, which help to load the file, it will perform some necessary process, and it will tell the engine to build a script module, also need to construct builder code for processing. If the code fails after this, then it will not have the memory to allocate the module. If the filename has been removed or the wrong name was given, or there is some unnecessary code has been written, then the builder was not able to load the file.

The last step is to identify the function which was defined that is to be called and have to set up the context for execution in code format. If that function could not be found, then need to write a print function to show a message of the function expecting.

Then has to create context, prepare it, and then execute it; if the execution didn’t work as expected, there is a need to write an exception code to handle the exception.

Example of AngelScript

Below is a very simple example that will give a brief overview of Handle:

}

Advantages

It has features like c/c++ that is static-typing, that uses the same static type as we use in c/c++ to make typing dynamic, and only additional type that we need to register here in angel-script.

It has an object handle feature that provides pointers, but pointers are not safe in scripting; hence it uses object handles instead of pointers; object handles in scripting control the lifetime of the object.

It has mod support in-game logic where it increases the life of the game.

Angelscript supports native calling conventions on major platforms, but there are some platforms that only work with generic calling conventions; generic calling is pure C++ that works everywhere.

The CScriptString used in angel-script cannot return the object value in native mode, which is not compatible.

There may be a memory leak issue.

Conclusion

In this article, we conclude that it is a scripting language and that has information about the application to accurately communicate with the c/c++ code; it has an inbuilt library hence making scripting language in our project is easy; in this article, we have seen some reasons to develop our program in more than one language.

Photoshop Layer Mask Tutorial With Example

What is a Photoshop Layer Mask?

Layer Mask is a very important part of Photoshop tools that gives the ability to hide and reveal parts of the layer without deleting them.

This is very efficient and non-destructive way of working. And it helps designers to become more efficient and more creative.

Let’s try to make an image with the help of layer mask .so that we can understand exactly what the layer mask works for.

I want to make a movie poster for a wellknown Hollywood movie “Avengers”. so let’s start working on it.

I’m using this image as background of the poster.

These all are images which we are going to use in this poster.

This is our background layer, and we will take all other images one by one and set them all in the sky portion of the background.

So let’s take the first one. i’m choosing iron man first. because I want to put him at the middle of the sky.

Scale the image and set it’s position properly.

Then take a photoshop layer mask for the image. Then grab the brush tool with smooth round brush. set the brush size,and start painting on the image to hide unwanted part of the image.

Look at the layer mask, its displays some black area in which you have painted,and the black color hides pixels.

Now go for the next image “Captain America”. And do the same process as we have done before on iron man image.

And do the same process again on the other 3 images which we are using In this file.

Let’s speed it up.

Now Put the ironman on the top of the layer panel. because it is on middle portion so it will not look good to be behind all other layers.

See, the bottom edges of all images are still sharp so it is looking very bad. so grab the brush tool and make all bottom edges blur, so that all images can look properly merged.

Once you have done with it, then select all five images and press CTRL + G to put them all in a single group.

And change the blend mode of that group to “screen” and look it is nicely blended with the sky.

Then make the image more effective with the help of “curve”.

Now we need to give a title to this poster. i have one image that we can use in this poster.

Scale and arrange the position of the image.

Now take a layer mask for this image. and start painting with black color and smooth round brush on unwanted parts of the image.

Remove that all black color around the name.

And then change the blending mode to “linear dodge”.

Drag it down below the curve layer.

Now save the file and take a look of it.

Its looks awesome.

We designed this poster very quick and easily with the help of layer mask.

So now just remember that black color hides pixels and white color reveals pixels.

So now u can understand how much important is photoshop masking layer tool.

This was the layer mask tool, now go ahead to the next topic “shape layer”.

Java Reflection Api Tutorial With Example

What is Reflection in Java?

Java Reflection is the process of analyzing and modifying all the capabilities of a class at runtime. Reflection API in Java is used to manipulate class and its members which include fields, methods, constructor, etc. at runtime.

The java.lang.reflect package provides many classes to implement reflection java.Methods of the java.lang.Class class is used to gather the complete metadata of a particular class.

Class in java.lang.reflect Package

Following is a list of various Java classes in java.lang.package to implement reflection-

Field: This class is used to gather declarative information such as datatype, access modifier, name and value of a variable.

Method: This class is used to gather declarative information such as access modifier, return type, name, parameter types and exception type of a method.

Constructor: This class is used to gather declarative information such as access modifier, name and parameter types of a constructor.

Modifier: This class is used to gather information about a particular access modifier.

Methods used in java.lang.Class

Public String getName (): Returns the name of the class.

public Class getSuperclass(): Returns the super class reference

Public Class[] getInterfaces() : Returns an array of interfaces implemented by the specified class

Public in getModifiers (): Returns an integer value representing the modifiers of the specified class which needs to be passed as a parameter to “public static String toString (int i )” method which returns the access specifier for the given class.

How to get complete information about a class

To get information about variables, methods, and constructors of a class, we need to create an object of the class.

public class Guru99ClassObjectCreation { public static void main (String[] args) throws ClassNotFoundException { Class c1 = Class.forName("Guru99ClassObjectCreation"); Guru99ClassObjectCreation guru99Obj = new Guru99ClassObjectCreation(); Class c2 = guru99Obj.getClass(); Class c3= Guru99ClassObjectCreation.class; } }

Following example shows different ways to create object of class “class” :

Example 1 : How to get Metadata of Class

Following example shows how to get metadata such as: Class name, super class name, implemented interfaces, and access modifiers of a class.

We will get the metadata of below class named Guru99Base.class:

import java.io.Serializable; public abstract class Guru99Base implements Serializable,Cloneable { }

Name of the class is: Guru99Base

It’s access modifiers are: public and abstract

It has implemented interfaces: Serializable and Cloneable

Since it has not extended any class explicitly, it’s super class is: java.lang.Object

Below class will get the meta data of Guru99Base.class and print it:

import java.lang.reflect.Modifier; public class Guru99GetclassMetaData { public static void main (String [] args) throws ClassNotFoundException { Class guru99ClassObj = Guru99Base.class; system.out.println("Name of the class is : " +guru99ClassObj.getName()); system.out.println("Name of the super class is : " +guru99ClassObj.getSuperclass().getName()); class[] guru99InterfaceList = guru99classObj.getInterfaces(); system.out.print("Implemented interfaces are : "); for (Class guru99class1 : quru99 InterfaceList) { system.out.print guru99class1.getName() + " "); } system.out.println(); int guru99AccessModifier= guru99classObj.getModifiers(); System.Out.println("Access modifiers of the class are : " +Modifier.tostring(guru99AccessModifier)); } }

print the name of the class using getName method

Print the name of the super class using getSuperClass().getName() method

Print the name of the implemented interfaces

Print the access modifiers used by the class

Example 2 : How to get Metadata of Variable

Following examples shows how to get metadata of variable:

Here, we are creating a class named Guru99VariableMetaData .class with some variables:

package guru; public class Guru99VariableMetaData { public static int guru99IntVar1=1111; static int guru99IntVar2=2222; static String guru99StringVar2="Learning Reflection API"; }

Steps to get the metadata about the variables in the above class:

Create the class object of the above class i.e. Guru99VariableMetaData.class as below:

Guru99VariableMetaData guru99ClassVar = new Guru99VariableMetaData(); Class guru99ClassObjVar = guru99ClassVar.getClass();

Get the metadata in the form of field array using getFields() or getDeclaredFields() methods as below:

Field[] guru99Field1= guru99ClassObjVar .getFields(); Field[] guru99Fiel2= guru99ClassObjVar .getDeclaredFields();

getFields() method returns metadata of the public variable from the specified class as well as from its super class.

getDeclaredFields() method returns metadata of the all the variables from the specified class only.

Get the name of the variables using “public String getName()” method.

Get the datatype of the variables using “public Class getType()” method.

Get the value of the variable using “public xxx get (Field)” method.

Here, xxx could be a byte or short of any type of value we want to fetch.

Get the access modifiers of the variables using getModifier() and Modifier.toString(int i) methods.

Here, we are writing a class to get the metadata of the variables present in the class Guru99VariableMetaData .class:

package guru; import java.lang.reflect.Field; public class Guru99VariableMetaDataTest { public static void main(String[] args) throws IllegalArgumentException, IllegalAccessException { Guru99VariableMetaData guru99ClassVar = new Guru99VariableMetaData(); Class guru99ClassObjVar = guru99ClassVar.getClass(); Field[] guru99Field1= guru99ClassObjVar.getDeclaredFields(); for(Field field : guru99Field1) { System.out.println("Variable name : "+field.getName()); System.out.println("Datatypes of the variable :"+field.getType()); int guru99AccessModifiers = field.getModifiers(); System.out.printlln("Access Modifiers of the variable : "+Modifier.toString(guru99AccessModifiers)); System.out.println("Value of the variable : "+field.get(guru99ClassVar)); System.out.println(); system.out.println("* * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * *") ; } } }

Created class object for Guru99VariableMetaData.class

Got all the metadata of the variables in a Field array

Printed all the variable names in the class Guru99VariableMetaData.class

Printed all the data types of the variables in the class Guru99VariableMetaData.class

Printed all the access modifiers of the variables in the class Guru99VariableMetaData.class

Printed values of all the variables in Printed all the data types of the variables in the class Guru99VariableMetaData.class

Example 3 : How to get Metadata of Method

Following examples shows how to get metadata of a method:

Here, we are creating a class named Guru99MethodMetaData .class with some methods

package guru; import java.sql.SQLException; public class Guru99MethodMetaData { public void guru99Add(int firstElement, int secondElement , String result) throws ClassNotFoundException, ClassCastException{ System.out.println("Demo method for Reflextion API"); } public String guru99Search(String searchString) throws ArithmeticException, InterruptedException{ System.out.println("Demo method for Reflection API"); return null; } public void guru99Delete(String deleteString) throws SQLException{ System.out.println("Demo method for Reflection API"); } }

Steps to get the metadata about the methods in the above class :

Create the class object of the above class i.e. Guru99MethodMetaData.class as below:

Guru99MethodMetaData guru99ClassVar = new Guru99MethodMetaData (); Class guru99ClassObjVar = guru99ClassVar.getClass();

Get method information in a Method array using getMethods() and getDeclaredMethods() method as below:

Method[] guru99 Method 1= guru99ClassObjVar .get Methods(); Method [] guru99 Method 2= guru99ClassObjVar .getDeclared Method s();

getMethods() method returns metadata of the public methods from the specified class as well as from its super class.

getDeclaredMethods() method returns metadata of the all the methods from the specified class only.

Get the name of the method using getName() method.

Get the return type of the method using getReturnType() method.

Get access modifiers of the methods using getModifiers() and Modifiers.toString(int i) methods.

Get method parameter types using getParameterTypes() method which returns a class array.

Get thrown exception using getExceptionTypes() method which returns a class array.

Here, we are writing a class to get the metadata of the methods present in the class Guru99MethodMetaData.class:

package guru; import java.lang.reflect.Method; import java.lang.reflect.Modifier; public class Guru99MethodMetaDataTest { public static void main (String[] args) { class guru99ClassObj = Guru99MethodMetaData.class; Method[] guru99Methods=guru99classObj.getDeclaredMethods(); for(Method method : guru99Methods) { System.out.println("Name of the method : "+method.getName()); System.out.println("Return type of the method : "+method.getReturnType()); int guru99ModifierList = method.getModifiers(); System.Out.printlin ("Method access modifiers : "+Modifier.toString(guru99ModifierList)); Class[] guru99ParamList= method.getParameterTypes(); system.out.print ("Method parameter types : "); for (Class class1 : guru99ParamList){ System.out.println(class1.getName()+" "); } System.out.println(); Class[] guru99ExceptionList = method. getExceptionTypes(); system.out.print("Excpetion thrown by method :"); for (Class class1 : guru99ExceptionList) { System.out.println (class1.getName() +" "): } System.Out.println(); system.out.println("* * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * "); } } }

Created class object for Guru99MethodMetaData.class

Got all the metadata of all the methods in a Method array

Printed all the method names present in the class Guru99MethodMetaData.class

Printed return types of the methods in the class Guru99MethodMetaData.class

Printed all the access modifiers of the methods in the class Guru99MethodMetaData.class

Printed parameter types of the methods in Guru99MethodMetaData.class

Printed exceptions are thrown by methods in Guru99MethodMetaData.class

Example 4 : How to get Metadata of Constructors

Following examples shows how to get metadata of constructors:

Here, we are creating a class named Guru99Constructor.class with different constructors:

package guru; import java.rmi.RemoteException; import java.sql.SQLException; public class Guru99Constructor { public Guru99Constructor(int no) throws ClassCastException ,ArithmeticException{ } public Guru99Constructor(int no, String name) throws RemoteException ,SQLException{ } public Guru99Constructor(int no, String name, String address) throws InterruptedException{ } }

Here, we are writing a class to get the metadata of the constructors present in the class Guru99Constructor.class:

package guru; import java.lang.reflect.Constructor; public class Guru99ConstructorMetaDataTest { public static void main (String[] args) { Class guru99Class=Guru99Constructor.class; Constructor[] guru99ConstructorList = guru99Class.getConstructors(); for (Constructor constructor : guru99ConstructorList) { System.out.println("Constrcutor name : "+constructor.getName()); int guru99Modifiers= constructor.getModifiers(); System.Out.printlin ("Constrctor modifier : "+Modifier.toString(guru99Modifiers)); Class[] guru99ParamList=constructor.getParameterTypes(); System.out.print ("Constrctor parameter types :"); for (Class class1 : guru99ParamList) { System.out.println(class1.getName() +" "); } System. out.println(); Class[] guru99ExceptionList=constructor.getFxceptionTypes(); System.out.println("Exception thrown by constructors :"); for (Class class1 : guru99ExceptionList) { System.out.println(class1.getName() +" "); } System.out.println(); System.out.println("*******************************************"); } } }

Created class object for Guru99Constructor.class

Got all the metadata of all the constructors in a Constructor array

Printed all the constructor’s names present in the class Guru99Constructor.class

Printed all the access modifiers of the constructors in the class Guru99Constructor.class

Printed parameter types of the constructors in Guru99Constructor.class

Printed exceptions are thrown by constructors in Guru99Constructor.class

Summary

Reflection programming in java helps in retrieving and modifying information about Classes and Class members such variable, methods, constructors.

Reflection API in Java can be implemented using classes in java.lang.reflect package and methods of java.lang.Class class.

Some commonly used methods of java.lang.Class class are getName (), getSuperclass (), getInterfaces (), getModifiers () etc.

Some commonly used classes in java.lang.reflect package are Field, Method, Constructor, Modifier, etc.

Reflection API can access private methods and variables of a class which could be a security threat.

What Is Semaphore? Counting, Binary Types With Example

What is Semaphore?

A semaphore either allows or disallows access to the resource, which depends on how it is set up.

In this Operating System (OS) tutorial, you will learn:

Characteristic of Semaphore

Here, are characteristic of a semaphore:

It is a mechanism that can be used to provide synchronization of tasks.

It is a low-level synchronization mechanism.

Semaphore will always hold a non-negative integer value.

Semaphore can be implemented using test operations and interrupts, which should be executed using file descriptors.

Types of Semaphores

The two common kinds of semaphores are

Counting semaphores

Binary semaphores.

Counting Semaphores

This type of Semaphore uses a count that helps task to be acquired or released numerous times. If the initial count = 0, the counting semaphore should be created in the unavailable state.

Counting Semaphores

Binary Semaphores

The binary semaphores are quite similar to counting semaphores, but their value is restricted to 0 and 1. In this type of semaphore, the wait operation works only if semaphore = 1, and the signal operation succeeds when semaphore= 0. It is easy to implement than counting semaphores.

Binary Semaphores

Example of Semaphore

The below-given program is a step by step implementation, which involves usage and declaration of semaphore.

Shared var mutex: semaphore = 1; Process i begin . . P(mutex); execute CS; V(mutex); . . End; Wait and Signal Operations in Semaphores

Wait for Operation

After the semaphore value is decreased, which becomes negative, the command is held up until the required conditions are satisfied.

Copy CodeP(S) { while (S<=0); S--; } Signal operation

This type of Semaphore operation is used to control the exit of a task from a critical section. It helps to increase the value of the argument by 1, which is denoted as V(S).

Copy CodeP(S) { S++; } Counting Semaphore vs. Binary Semaphore

Here, are some major differences between counting and binary semaphore:

Counting Semaphore Binary Semaphore

No mutual exclusion Mutual exclusion

Any integer value Value only 0 and 1

More than one slot Only one slot

Provide a set of Processes It has a mutual exclusion mechanism.

Difference between Semaphore vs. Mutex

Parameters Semaphore Mutex

Mechanism It is a type of signaling mechanism. It is a locking mechanism.

Data Type Semaphore is an integer variable. Mutex is just an object.

Modification The wait and signal operations can modify a semaphore. It is modified only by the process that may request or release a resource.

Resource management If no resource is free, then the process requires a resource that should execute wait operation. It should wait until the count of the semaphore is greater than 0. If it is locked, the process has to wait. The process should be kept in a queue. This needs to be accessed only when the mutex is unlocked.

Thread

Ownership Value can be changed by any process releasing or obtaining the resource. Object lock is released only by the process, which has obtained the lock on it.

Types Types of Semaphore are counting semaphore and binary semaphore and Mutex has no subtypes.

Operation Semaphore value is modified using wait () and signal () operation. Mutex object is locked or unlocked.

Resources Occupancy In case if the object is already locked, the process requesting resources waits and is queued by the system before lock is released.

Advantages of Semaphores

Here, are pros/benefits of using Semaphore:

It allows more than one thread to access the critical section

Semaphores are machine-independent.

Semaphores are implemented in the machine-independent code of the microkernel.

They do not allow multiple processes to enter the critical section.

As there is busy waiting in semaphore, there is never a wastage of process time and resources.

They are machine-independent, which should be run in the machine-independent code of the microkernel.

They allow flexible management of resources.

Here, are cons/drawback of semaphore

One of the biggest limitations of a semaphore is priority inversion.

The operating system has to keep track of all calls to wait and signal semaphore.

Their use is never enforced, but it is by convention only.

In order to avoid deadlocks in semaphore, the Wait and Signal operations require to be executed in the correct order.

Semaphore programming is a complicated, so there are chances of not achieving mutual exclusion.

Semaphore is more prone to programmer error.

It may cause deadlock or violation of mutual exclusion due to programmer error.

Summary:

It is a mechanism that can be used to provide synchronization of tasks.

Counting semaphore uses a count that helps task to be acquired or released numerous times.

The binary semaphores are quite similar to counting semaphores, but their value is restricted to 0 and 1.

Signal semaphore operation is used to control the exit of a task from a critical section

Counting Semaphore has no mutual exclusion whereas Binary Semaphore has Mutual exclusion

Semaphore means a signaling mechanism whereas Mutex is a locking mechanism

Semaphore allows more than one thread to access the critical section

One of the biggest limitations of a semaphore is priority inversion.

How Does Covenant Work With Example And Types?

What is Covenant?

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Explanation of Covenant

One of the major concerns for a lender is the complete recovery of the loan from the borrower. It has been observed that in cases where no restrictions are imposed on the borrower, there is a high probability that the management of the borrower company will completely ignore the lender’s interest and make confident decisions that will jeopardize their future debt servicing ability. So, covenants are tools lenders use to ensure their money is safe. These legal bindings ensure that the borrowers abide by certain pre-decided conditions, or the default clause will be triggered per the agreement. So, if the borrower breaches any of the covenants, the debt agreement allows the lender to demand repayment immediately.

In most cases, financial covenants are expressed in ratio ceiling or floor. For example, the debt-to-equity ratio shouldn’t breach the ceiling of 1.5x, or the interest coverage ratio shouldn’t breach the floor of 2.2x. However, covenants are not just restricted to financial ratios. They can cover many other aspects of company operations, such as maximum dividend payment, working capital requirement, retention of critical employees, etc.

How Does Covenant Work?

Now, let us look at how covenant works in a company setup.

Corporations often require money to expand their business or support their daily operations. In cases where they wish to raise funds at a lower cost, they opt for bond issuance or bank debt and pay interest on the borrowed money. In such a scenario, one of the primary concerns of the lender is the protection of their money against default.

So, the lenders then set some covenants that are legal agreements between the lender and the borrower. These impose pre-determined conditions before the issuance of the bonds. Now, if the borrower agrees with the terms and conditions of the debt agreement, the lender will only go ahead with the lending. In addition, the covenants take cognizance of the rating of the company and the debt instrument. So, these covenants add extra protection for the lender’s money.

For instance, the lender imposes a covenant that mandates that the debt-to-equity ratio shouldn’t exceed 1.5x. However, the borrower incurred heavy losses in the current year, resulting in equity erosion, pushing the debt-to-equity ratio beyond the threshold of 1.5x. The debt agreement states it is a breach and will trigger a default. So, in this case, the covenant acts as an early warning signal for the lender that the borrower’s business is in trouble which may result in liquidity problems. Hence, it is better to call back the borrowed amount immediately.

Example of Covenant

Let us take the example of ABC Inc., which is planning to raise $50 million through the issuance of bonds at the beginning of 2023. Now, the company has approached many lenders to discuss the terms and conditions of lending. As a result, some banks agreed to purchase the bonds after adequately evaluating the creditworthiness of ABC Inc. However, all the banks proposed the following covenants before buying the bonds.

These bonds (until their maturity) must be the senior most debt in the company’s capital structure.

The company’s interest coverage ratio (EBITDA/ Interest expense)must never fall below 3.0x

The company’s debt-to-equity ratio cannot exceed the ceiling of 1.2x

Solution:

Now, let us take the example mentioned in the above section and determine whether any of the covenants have been breached if the following annual financial figures were reported at the end of 2023:

EBITDA = $10 million

Interest expense = $3 million

Outstanding debt = $60 million

Total equity = $55 million

Interest Coverage Ratio = EBITDA / Interest Expense

Interest Coverage Ratio = $10 million / $3 million

Interest Coverage ratio = 3.33x, which is more than the covenant of 3.0x

Again, we can calculate the debt-to-equity ratio of the company as follows:

Debt-to-Equity Ratio = Outstanding Debt / Total Equity

Debt-to-Equity Ratio = $60 million / $55 million

Debt-to-Equity Ratio = 1.09x, which is below the covenant of 1.2x

So, none of the covenants has been breached.

Types of Covenant

1. Affirmative covenants: This type of clause requires the borrower to perform certain specific actions, and if the borrowers fail to do so, then it is in outright default. However, lenders may offer borrowers a grace period, and if the borrower fails to comply within that period, it considers a default. Some examples of affirmative covenants include furnishing audited financial statements to the lender at regular intervals, maintaining proper accounting books, etc.

2. Negative covenants: This type of covenant is imposed on the borrower to refrain from undertaking any such actions that may lead to the deterioration of their debt serviceability. Some examples of negative covenants include maintenance of dividend payout below 50%, maintenance of gearing below 3.0x, etc.

Conclusion

So, it can be seen that covenants are significant from the point of view of the lenders. Covenants impose discipline on companies and offer better control to the lenders. However, it should be noted that too many covenants may end up restricting the company’s operations, which can be detrimental to its revenue growth and profitability.