A REPORT

OF
SIX WEEKS INDUSTRIAL TRAINING
at
INCAPP INSTITUTE, Gr. Noida
SUBMITTED
IN PARTIAL FULFILLMENT OF THE REQUIREMENT FOR THE AWARD
OF THE DEGREE OF

BACHELOR OF TECHNOLOGY
(Information Technology)

JUNE 2019 – JULY 2019

SUBMITTED BY:
DIVYA SUNDRIYAL
1619213035
DEPARTMENT OF INFORMATION TECHNOLOGY

G L BAJAJ INSTITUTE OF TECHNOLOGY AND MANAGEMENT,

GREATER NOIDA
(Affiliated to AKTU University, Lucknow)
CONTENT
TOPIC PAGE NO.

Candidate’s Declaration 1
Abstract 2
Acknowledgement 3
Introduction 4
Training Work Undertaken 14
Implementation and Testing 19
Conclusion 24
 CANDIDATE’S DECLARATION

I “DIVYA SUNDRIYAL” hereby declare that I have undertaken six weeks industrial training
at “INCAPP, Gr. Noida” during a period from June to July in partial fulfillment of
requirements for the award of degree of B. Tech(Information Technology) at G L BAJAJ
INSTITUTE OF TECHNOLOGY AND MANAGEMENT, Gr. Noida. The work which is
being presented in the training report submitted to the Department of Information Technology
at G L Bajaj Institute of Technology and Management, Gr. Noida is an authentic report of
training report.

Signature of the Student

The six weeks industrial training Viva-voce Examination of has been held on
and accepted.

Ms. EIRTTY KAPOOR

(Internal Examiner)
 ABSTRACT

Employee Management System is a distributed application, developed to maintain the details

of employees working in any organization. It maintains the information about the personal
details of their employees, also the details about the payroll system which enable to generate
the payslip. The application is actually a suite of applications developed using Java.
It is simple to understand and can be used by anyone who is not even familiar with simple
employees system. It is user friendly and just asks the user to follow step by step operations by
giving him few options. It is fast and can perform many operations of a company.
This software package has been developed using the powerful coding tools of JAVA at Front
End and Microsoft SQL Server at Back End. The software is very user friendly. The package
contains different modules like Employee details. This version of the software has multi-user
approach. For further enhancement or development of the package, user’s feedback will be
considered.
 ACKNOWLEDGEMENT

I express my Gratitude to Mr. Arjun Singh for his help, guidance throughout the work for this
project without which I would not have been able to complete this project to such a success.
I would also like to thank Mr. P.C Vashisht (H.O.D, Information Technology) who inspired
me directly or indirectly in accomplishing this project work.
Finally, I would also like to thank other faculty members who provided me with Moral
support during the course of this project.
 INTRODUCTION

OBJECTIVE

This software application stores all the employee's information in a database. It is an

application developed in Java GUI technology and database used is SQLite. It contains
employee information like employee id, first name, surname, and age. It is an easy to use
application and has a user-friendly interface. It is totally built at the administrative end which
means that only the admin has access rights to change or modify any records. So, this makes it
safe and reliable application to use.
The main aim of developing this application was to reduce the errors that occur in the manual
system. One can search the details easily by just entering employee id. In earlier systems, there
was not such a facility to do so. All the details are stored in an SQLite database. It is easy to
update any employee details. All the employee records are integrated and so this makes it user-
friendly and easy to use application.

LANGUAGE USED – JAVA

Java is a platform independent language. Its created applications can be used on a standalone
machine as well as on distributed network. More over applications developed in java can be
extended to Internet based applications. Thus, java was chosen as background to design this
application.
Java is a general computer programming language developed by Sun Microsystems. Originally
called "Oak", by its inventor James Gosling, Java was designed with several innovative
features. These include a language that is entirely object oriented, and the ability to write an
application once and move it to virtually any platform.
INNOVATIONS

The benefits of object-oriented programming are not necessarily obvious to non-programmers.

Essentially what this means to managers is that code written in Java will be easier to maintain
and reuse in the long run. The downside is that object-oriented programming requires better
planning from the beginning of a project, and may increase the amount of initial development
time a project requires. For this reason alone, Java is rarely a good choice for small projects.

The second innovation that Java provides, platform neutrality, is perhaps the greatest reason
for its wide acceptance. The fact that Java was originally intended a language for writing
device controllers for items such as garage openers and microwave ovens is the key reason for
this. In practice, however, this ability has been more useful in writing enterprise class business
applications, where mission critical software may be required to run on a variety of platforms
over its lifetime. Theoretically at least, once compiled, a Java binary should be able to run on
any machine that also has a piece of software called a Java Virtual Machine. In reality, this is
not always the case. However, more often than not Java does succeed in this regard, whereas
this is impossible with an application written in a language such as C++.

JAVA IN WEB DEVELOPMENT

In terms of web development, Java is frequently used in two ways. Most commonly Java is
used to write server-side web applications using two technologies: JSPs and servlets.
Using Java in this capacity is a good choice for complex applications, that will have large
numbers (~1000+) of concurrent users, and will be developed by a team of programmers.
Less complex projects, with fewer concurrent users may have better outcomes when
developed in procedural scripting language like php.

The second way in which Java is used, is to create special, browser embeddable, programs
called Applets. While applets had a brief period of acceptance, their use is becoming
increasingly rare, being replaced by a number of technologies such a Flash and JavaScript,
which are more effective at providing design enhancements such as animation and rollovers.
Using applets for these purposes is a mistake frequently made by beginning developers. Still,
Applets do have a place in writing specialized browser-based applications that cannot be
accomplished by these other technologies. Careful consideration should be made before
approving any project that uses Applets.
ORIGIN AND GROWTH

Like many recently developed computer languages, Java borrows much of its language design
from C/C++. For that reason, many programmers who are proficient in those languages have
leaned Java, and provide a large pool of qualified developers. Java has gained additional
ground as a first language, as it is generally simpler to master than C++, another commonly
used programming language.

CLASSES AND OBJECTS

CLASSES

In the real world, you'll often find many individual objects all of the same kind. There may be
thousands of other bicycles in existence, all of the same make and model. Each bicycle was
built from the same set of blueprints and therefore contains the same components. In object-
oriented terms, we say that your bicycle is an instance of the class of objects known as bicycles.
A class is the blueprint from which individual objects are created.

OBJECTS

Objects are key to understanding object-oriented technology. Look around right now and
you'll find many examples of real-world objects: your dog, your desk, your television set,
your bicycle.

Real-world objects share two characteristics: They all have state and behavior. Dogs have
state (name, color, breed, hungry) and behavior (barking, fetching, wagging tail). Bicycles
also have state (current gear, current pedal cadence, current speed) and behavior (changing
gear, changing pedal cadence, applying brakes). Identifying the state and behavior for real-
world objects is a great way to begin thinking in terms of object-oriented programming.

Take a minute right now to observe the real-world objects that are in your immediate area.
For each object that you see, ask yourself two questions: "What possible states can this object
be in?" and "What possible behavior can this object perform?". Make sure to write down your
observations. As you do, you'll notice that real-world objects vary in complexity; your
desktop lamp may have only two possible states (on and off) and two possible behaviors (turn
on, turn off), but your desktop radio might have additional states (on, off, current volume,
current station) and behavior (turn on, turn off, increase volume, decrease volume, seek, scan,
and tune). You may also notice that some objects, in turn, will also contain other objects.
These real-world observations all translate into the world of object-oriented programming.

Software objects are conceptually similar to real-world objects: they too consist of state and
related behavior. An object stores its state in fields (variables in some programming languages)
and exposes its behavior through methods (functions in some programming languages).
Methods operate on an object's internal state and serve as the primary mechanism for object-
to-object communication. Hiding internal state and requiring all interaction to be performed
through an object's methods is known as data encapsulation — a fundamental principle of
object-oriented programming.

By attributing state (current speed, current pedal cadence, and current gear) and providing
methods for changing that state, the object remains in control of how the outside world is
allowed to use it. For example, if the bicycle only has 6 gears, a method to change gears could
reject any value that is less than 1 or greater than 6.

Bundling code into individual software objects provides a number of benefits, including:

1. Modularity: The source code for an object can be written and maintained
independently of the source code for other objects. Once created, an object can be easily
passed around inside the system.

2. Information-hiding: By interacting only with an object's methods, the details of its

internal implementation remain hidden from the outside world.

3. Code re-use: If an object already exists (perhaps written by another software

developer), you can use that object in your program. This allows specialists to
implement/test/debug complex, task-specific objects, which you can then trust to run in
your own code.

4. Pluggability and debugging ease: If a particular object turns out to be problematic,

you can simply remove it from your application and plug in a different object as its
replacement. This is analogous to fixing mechanical problems in the real world. If a
bolt breaks, you replace it, not the entire machine.

INHERITANCE

Different kinds of objects often have a certain amount in common with each other. Mountain
bikes, road bikes, and tandem bikes, for example, all share the characteristics of bicycles
(current speed, current pedal cadence, current gear). Yet each also defines additional features
that make them different: tandem bicycles have two seats and two sets of handlebars; road
bikes have drop handlebars; some mountain bikes have an additional chain ring, giving them a
lower gear ratio.
Object-oriented programming allows classes to inherit commonly used state and behaviour from
other classes. For example, Bicycle becomes the superclass of MountainBike, RoadBike, and
TandemBike. In the Java programming language, each class is allowed to have one direct superclass,
and each superclass has the potential for an unlimited number of subclasses.

INTERFACE

As you've already learned, objects define their interaction with the outside world through the
methods that they expose. Methods form the object's interface with the outside world; the
buttons on the front of your television set, for example, are the interface between you and the
electrical wiring on the other side of its plastic casing. You press the "power" button to turn the
television on and off.

In its most common form, an interface is a group of related methods with empty bodies. A
bicycle's behavior, if specified as an interface, might appear as follows:

interface Bicycle {
void changeCadence(int newValue);

void changeGear(int newValue);

void speedUp(int increment);

void applyBrakes(int decrement);

}
To implement this interface, the name of your class would change (to ACMEBicycle, for
example), and you'd use the implements keyword in the class declaration:

class ACMEBicycle implements Bicycle {

// remainder of this class implemented as before

Implementing an interface allows a class to become more formal about the behaviour it
promises to provide. Interfaces form a contract between the class and the outside world, and
this contract is enforced at build time by the compiler. If your class claims to implement an
interface, all methods defined by that interface must appear in its source code before the class
will successfully compile.
PACKAGE

A package is a namespace that organizes a set of related classes and interfaces. Conceptually
you can think of packages as being similar to different folders on your computer. You might
keep HTML pages in one folder, images in another, and scripts or applications in yet another.
Because software written in the Java programming language can be composed of hundreds or
thousands of individual classes, it makes sense to keep things organized by placing related
classes and interfaces into packages.

The Java platform provides an enormous class library (a set of packages) suitable for use in
your own applications. This library is known as the "Application Programming Interface", or
"API" for short. Its packages represent the tasks most commonly associated with general-
purpose programming. For example, a String object contains state and behavior for character
strings; a File object allows a programmer to easily create, delete, inspect, compare, or modify
a file on the filesystem; a Socket object allows for the creation and use of network sockets;
various GUI objects control buttons and checkboxes and anything else related to graphical user
interfaces. There are literally thousands of classes to choose from. This allows you, the
programmer, to focus on the design of your particular application, rather than the infrastructure
required to make it work.

The Java Platform API Specification contains the complete listing for all packages, interfaces,
classes, fields, and methods supplied by the Java Platform 6, Standard Edition. Load the page
in your browser and bookmark it. As a programmer, it will become your single most important
piece of reference documentation.

GUI SWING WIDGETS

A Graphical User Interface (GUI) is a visual paradigm which allows a user to communicate
with a program in an intuitive way. Its main features are widgets (aka controls) and event driven
activities. Clients expect a graphical interface in an application.

Java has two GUI packages, the original Abstract Windows Toolkit (AWT) and the newer
Swing. AWT uses the native operating system's window routines and therefore the visual effect
is dependent on the run-time system platform. But this is contrary to the concept of having a
virtual model. Swing allows three modes: a unified 'Java' look and feel [the default], the native
platform look, or a specific platform's look. Swing is built on the original objects and
framework of AWT. Swing components have the prefix J to distinguish them from the original
AWT ones (eg JFrame instead of Frame). To include Swing components and methods in your
project you must import the java.awt.*, java.awt.event.*, and javax.swing.* packages.
CONTAINERS, FRAMES AND CONTENT PANES

Containers are widgets (GUI controls) that are used to hold and group other widgets such as
text fields and checkboxes. Displayable frames are top-level containers such as JFrame,
JWindow, JDialog, JApplet and JInternalFrame which interface to the operating system's
window manager. Non-displaying content panes are intermediate containers such as JPanel,
JOptionPane, JScrollPane, JLayeredPane, JSplitPane and JTabbedPane which organize the
layout structure when multiple controls are being used.

JWindow is an unadorned container that has been superceded for the most part by JDialog.
However, it does provide a useful container for a splash screen.

COMMON WIDGET METHODS

Several methods can be used with many different controls. These include: add(),
requestFocus(), setToolTipText().

JFRAME AND JPANEL

JFrame is the most commonly used top-level container. It adds basic functionality such as
minimize, maximize, close, title and border to basic frames and windows. Some important
JFrame methods are: setBounds(x,y,w,h), setLocation(x,y), setSize(w,h), setResizable(bool),
setTitle(str), setVisible(bool), isResizable() and getTitle(). The
setDefaultCloseOperation(constant) method controls the action that occurs when the close icon
is clicked. Normally the constant used is JFrame.EXIT_ON_CLOSE.

JPanel is the most commonly used content pane. An instance of the pane is created and then
added to a frame. The add() method allows widgets (GUI components) to be added to the pane.
The way they are added is controlled by the current layout manager.

LABELS, ICONS AND BUTTONS

Labels are non-interactive text objects most commonly used as prompts. They are created using
the JLabel() constructor with the required text as the first parameter. Another parameter can
be added using a SwingConstant value to set horizontal alignment. Vertical alignment is
through the setVerticalAlignment() method. The contents of a label can be changed with the
setText() method.

Icons can be easily added to labels or other controls either to brand, dress up, or aid
accessibility. Icons are constructed from the ImageIcon class and then added as a parameter to
the label (or other) control. An extra parameter can be used to control the position of the text
relative to the icon. It must use one of the SwingConstants values.

Simple buttons are used to start operations. They are created with the JButton() constructor.
They can be deactivated with the setEnabled(false) method and tested with the isEnabled()
method. One useful button method is setMnemonic(char) which allows a hot key to be
associated with the button

Simple buttons require an ActionEvent event listener that reacts to the button click.
Toggle buttons are a visual push on - push off mechanism. They are created with the
JToggleButton() constructor. The isSelected() method returns the state of the button. And in
addition to ActionEvent, the ChangeEvent is triggered.

EVENT LISTENERS

GUIs are event-based. That is they respond to buttons, keyboard input or mouse activities. Java
uses event listeners to monitor activity on specified objects and react to specific conditions.
For a listing of useful event listeners check the appendix. For techniques on organizing many
different events in larger projects, view advanced event listeners.

The first step in adding a basic button push event handler to the above example is to import
awt.event.* which contains all of the event classes. Next add the phrase implements
ActionListener to the class header. Register event listeners for each button widget using the
addActionListener(this) method.
 Training work undertaken

The aim of the system is to develope “EMPLOYEE MANAGEMENT SYSTEM”

software, which should automate the process to create and store employee details . The
system is supposed to be used as a subsystem in a large office system, which could be manual
system or a computerized one. Therefore, the proposed system must be able to function under
both circumstances.

The proposed system is not a freeware and due to the usage of swings, becomes user interactive.

 The project demand a page of employee details that include:

 Employees personel detail.
 Employees salary, allowances, deductions.
HARDWARE AND SOFTWARE REQUIREMENTS

Hardware Requirements
 MEMORY SPACE:
Minimum - 32 MB

Recommended - - 64 MB

 HDD - To install the software at least 2 GB and the data storage is

depending upon the organizational setup.

 PROCESSOR - Intel Pentium IV, 1GHZ or above

 RAM - 256MB or above

 VIDEO - 1024x768, 24-bit colors

 KEYBOARD - Standard 104 Keys(QWERTY)

 Blank writable CD to keep the backup of the Package.

Software Requirements

 OPERATING SYSTEM - Windows XP Professional

 DEVELOPING LANGUAGE - JAVA (jdk-5)

 DATABASE - MICROSOFT SQL SERVER 2005

TOOLS, PLATFORM AND LANGUAGE USED

FRONT END:

The programming has been done using the language Java. It is Sun Microsystem’s strategic
language for platform independent programming. It is easy to use, efficient and flexible. This
language is preferred because one can build a program using this object oriented and platform
independent programming with less effort than with any other programming language. It’s a
natural language for building database applications, owing to the level and sophistication of
the tools included with the language.

BACK END:

Microsoft Sql Server is one of the leading database management systems available on the
market today. It is easy to use and administer, and it comes with tools and wizards that make it
easy to develop applications. The database itself has been redesigned to automatically perform
many tuning functions, leaving you free to focus on most important tasks.
PLATFORM USED:

Windows (Operating System)

a) Window derived from its name from the on-screen “WINDOWS” that it used to
display information’s.

b) Windows XP Professional is a multi-user operating system. It has been designed and

developed by Microsoft Co-operation.

c) When a computer is switch on for working, it needs the operating system because
all the activities of a system are supervised by the operating system.

The features of the operating system are:-

1. Provides an interactive environment.

2. Graphical user interfaces.

i. The Commands are displayed on the screen and we don’t have to

remember all commands.
ii. GUI makes it easy to work with disks and directories. It can display tree
like diagram of directories, directories sub-0 directories on hard disk.

3. Point and Click.

4. User friendly.
 SYSTEM DESIGN

LOGIN SCREEN

MENU SCREEN

ADD EMPLOYEE EMPLOYEE LIST VIEW DETAILS GENERATE SLIP EXIT

Name Add Post Experience Edit DELETE BACK

rres
s
OK
Salary House
SYSTEM TESTING

During systems testing, the system is used experimentally to ensure that the software does not
fail. In other words, we can say that it will run according to its specifications and in the way
users expect. Special test data are input for processing, and the results examined. A limited
number of users may be allowed to use the system so that analyst can see whether they try to
use it in unforeseen ways. It is desirable to discover any surprises before the organization
implements the system and depends on it.

Software modules are tested for their functionality as per the requirements identified during
the requirements analysis phase. To test the functionality of the file transfer and chat
application, a Quality Assurance (QA) team is formed. The requirements identified during the
requirements analysis phase are submitted to the QA team. In this phase the QA team tests the
application for these requirements. The development team submits a test case report to the QA
team so that the application can be tested in the various possible scenarios.

The software development project, errors can be injected at any stage during development i.e.
if there is an error injected in the design phase then it can be detected in the coding phase
because there is the product to be executed ultimately on the machine, so we employ a testing
process.

During the testing the program to be tested is executed with certain test cases and output of
these test cases is evaluated to check the correctness of the program. It is the testing that
performs first step in determining the errors in the program.

Test Cases and Test Criteria

During Test Cases that are good at revealing the presence of faults is central to successful
testing. The reason for this is that if there is a fault in the program, the program can still provide
the expected behavior on the certain inputs. Only for the set of inputs the faults that exercise
the fault in the program will the output of the program devise from the expected behavior.
Hence, it is fair to say that testing is as good as its test case.

The number of test cases used to determine errors in the program should be minimum. There
are two fundamental goals of a practical testing activity:-
 maximize the number of errors detected and.
 minimize the number of test cases.
As these two goals are contradictory so the problem of selecting test cases is a complex one.
While selecting the test cases the primary objective is to ensure that if there is an error or fault
in the program, it is exercised by one of its test cases. An ideal test case is one which succeeds
(meaning that there are no errors, revealed in its execution) only it there are no errors in the
program one possible set of ideal test cases is one which includes all the possible inputs to the
program. This is often called "exhaustive testing", however it is impractical and infeasible as
even a small program can have an infinite input domain.

So to avoid this problem we use "test criteria" in selection of the test cases. There are two
aspects of the test case selection:-

 specifying a criteria for evaluating the test cases

 generating the set of cases that satisfy a given criteria.

The fully automated process of generating test criteria has not been yet found rather guidelines
are only the automated tool available to us previously. The two fundamental properties for a
testing criterion are:-
 Reliability: a criterion is reliable if all the sets that satisfy the criteria detect the same
error. .
 Validity: a criterion is valid if for any error in the program there is some set satisfying
the criteria that will reveal the error.

The fundamental theorem of testing is that if a testing criterion is valid and reliable, if a set
satisfying criteria succeeds then the program contains no errors.

APPROACHES TO TESTING

There are two fundamental approaches to testing they are:

FUNCTIONAL Testing/Black Box Testing:

In functional testing the structure of the program is not considered. Test cases are solely
determined on the basis of requirement or specification of the program or module. Internals of
the modules and the programs are not considered for selection of test cases. Due to this nature
it is also called "black box testing".
The most obvious functional testing procedure is "exhaustive testing", which is impractical.
The other criteria for generating the test case are to generate them "randomly" this strategy has
a little chance of resulting in a test case that is close to optimal.
There is no appropriate criterion for developing the test case so we have certain heuristic
approaches-:

a) Equivalence Class Partitioning: in which the domain of all inputs is divided into a set of
equivalence classes, so that if any test in that class succeeds, then every test in that class will
succeed i.e. the success of one set element implies the success of the other.

b) Boundary Value Analysis: It has been observed that programs work correctly for a set of
values in an equivalence class fail on certain values. These values generally lie on the boundary
of equivalence class. So in the boundary value analysis we chose an input for a test case from
an equivalence class, such that input lies on the edge of equivalence class. Boundary value test
cases are also called "extreme cases".

c) Cause-Effect Graphing: The problem with the prior approaches is that they consider each
input separately i.e. both concentrate on classes and conditions of one input. The combination
of inputs is not considered which is used in many cases. One way to exercise the combination
of various input conditions is to consider all the valid combinations of the equivalence class of
the input conditions. The technique starts with identifying the causes and the effect of system
under testing.

STRUCTURAL TESTING:

In the structural approach the test cases are generated an the basis of the actual code of the
program or the module to be tested, This structural approach is sometimes called "glass box
testing", This testing is concerned with the implementation of the program. The content is not
to exercise the various input conditions rather different programming structures and data
structures used in the program.
There are three different approaches to structural testing they are- :

a) Control flow based criteria:

Most common structure based criteria use control flow based testing in which the control flow
graph of the program is considered and coverage of various aspects of graph are specified as
criteria. The various control flow based strategies are
 statement coverage,
 branch coverage and
 all path coverage

b) Data Flow based testing:

The basic idea behind the data flow based testing is to make sure that during testing, the
definitions of variables and their subsequent use is tested. To implement the data flow based
testing the data flow graph is first made from the control flow graph.

c) Mutation Testing:

In the above two testing techniques the focus is on which path to be executed, but mutation
testing is not a path-based approach. The mutation testing requires that the set of test cases
must be such that they can distinguish between the original programs and is mutants. In
software world there is no fault model as in hardware so most of the techniques do guess work
regarding where the fault must lie and then select the test cases to reveal those faults. In
Mutation testing faults of some pre-decided types are introduced in the program being tested.
Then those faults are found in the mutants.
 Implementation, Evaluation And Testing

Implementation is the process of having systems personnel check out and put new equipment
into use, train users, install the new application and construct any files of data needed to use it.
This phase is less creative than system design. Depending on the size of the organization that
will be involved in using the application and the risk involved in its use, systems developers
may choose to test the operation in only one area of the firm with only one or two persons.
Sometimes, they will run both old and new system in parallel way to compare the results. In
still other situations, system developers stop using the old system one day and start using the
new one the next.

Evaluation of the system is performed to identify its strengths and weaknesses. The actual
evaluation can occur along any of the following dimensions:

1. Operational Evaluation: Assessment of the manner in which the system functions,

including case of use, response time, overall reliability and level of utilization.
2. Organizational Impact: Identification and measurement of benefits to the
organization in such areas as financial concerns, operational efficiency and competitive
impact.
3. User Manager Assessment: Evaluation of the attitudes of senior and user manager
within the organization, as well as end-users.
4. Development Performance: Evaluation of the development process in accordance
with such yardsticks as overall development time and effort, conformance to budgets
and standards and other project management criteria.

Maintenance is necessary to eliminate errors in the working system during its working life
and to tune the system to any variations in its working environment often small system
deficiencies are found as a system is brought into operations and changes are made to remove
them. System planners must always plan for resource availability to carry out these
maintenance functions. The importance of maintenance is to continue to bring the new system
to standards.
 CONCLUSION

Since this project has been designed exclusively as a project, certain complexities that do faced
by any real life manual problem like total no. of employee, address redundancy etc. are
considered in this project. But enhancement to the project can easily be made without changing
the current design and programming structure.