Essayit

Essayit

Introduction To Design Patterns

Design Patterns In Java

Bob Tarr

What Is A Pattern?
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Current use comes from the work of the architect Christopher Alexander Alexander studied ways to improve the process of designing buildings and urban areas “Each pattern is a three-part rule, which expresses a relation between a certain context, a problem and a solution.” Hence, the common definition of a pattern: “A solution to a problem in a context.” Patterns can be applied to many different areas of human endeavor, including software development

Design Patterns In Java

Introduction To Design Patterns
2

Bob Tarr

1

Why Patterns?
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"Designing object-oriented software is hard and designing reusable object-oriented software is even harder." - Erich Gamma Experienced designers reuse solutions that have worked in the past Well-structured object-oriented systems have recurring patterns of classes and objects Knowledge of the patterns that have worked in the past allows a designer to be more productive and the resulting designs to be more flexible and reusable

Design Patterns In Java

Introduction To Design Patterns
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Bob Tarr

Software Patterns History
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1987 - Cunningham and Beck used Alexander’s ideas to develop a small pattern language for Smalltalk 1990 - The Gang of Four (Gamma, Helm, Johnson and Vlissides) begin work compiling a catalog of design patterns 1991 - Bruce Anderson gives first Patterns Workshop at OOPSLA 1993 - Kent Beck and Grady Booch sponsor the first meeting of what is now known as the Hillside Group 1994 - First Pattern Languages of Programs (PLoP) conference 1995 - The Gang of Four (GoF) publish the Design Patterns book

Design Patterns In Java

Introduction To Design Patterns
4

Bob Tarr

2

Types Of Software Patterns
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Analysis Design Organizational Process Project Planning Configuration Management

Design Patterns In Java...