The document discusses the four types of Java access modifiers - private, default, protected, and public. It defines what access each modifier allows within and outside of a class and package. A table is provided comparing the scope of access for each modifier, such as private only allowing access within the class, while public allows access everywhere. Encapsulation is also summarized as the process of wrapping code and data together, providing advantages like making classes read-only or write-only and achieving data hiding.

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Access Modifiers.
• It defines the accessibility or scope of a field, method, constructor, or class.
• There are four types of Java access modifiers:
✓ Private
✓ Default
✓ Protected
✓ Public

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Private.
• The access level of a private modifier is only within the class.
• It cannot be accessed from outside the class.

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Default.
• The access level of a default modifier is only within the package.
• It cannot be accessed from outside the package.
• If you do not specify any access level, it will be the default.

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Protected.
• The access level of a protected modifier is within the package and outside the
package through child class.
• If you do not make the child class, it cannot be accessed from outside the package.

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Public.
• The access level of a public modifier is everywhere.
• It can be accessed from within the class, outside the class, within the package and
outside the package.

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Comparison.
Access
Modifier
within class
within
package
outside
package by
subclass only
outside
package
Private Y N N N
Default Y Y N N
Protected Y Y Y N
Public Y Y Y Y

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Encapsulation.
• It is a process of wrapping code and data together into a single unit.
• The Bean class is the example of a fully encapsulated class.
ADVANTAGES:
• It can make the class read-only or write-only.
• It provides you the control over the data.
• It is a way to achieve data hiding.