Example of Source Code in Java

In software engineering, source code is the fundamental material that makes up a program. In this example, we will explore some fictive examples of source code in Java.

A good starting point would be `new LinkedHashMap(LinkedHashSet, List)`, which returns an unmodifiable linked map that doesn't clone the items, but uses them. This demonstrates the concept of structural patterns, specifically the adapter pattern.

Another example is `adapters.XmlAdapter#marshal()` and `#unmarshal()`, which can bridge different abstract/interface types by delegating to another instance. This is a clear manifestation of the adapter pattern in Java.

Similarly, `java.io.OutputStreamWriter(OutputStream)` (which returns a Writer) and `java.io.InputStreamReader(InputStream)` (which returns a Reader) illustrate structural patterns such as adapters.

Furthermore, we can observe singleton design patterns in various Java APIs. For instance, `java.net.URLStreamHandlerFactory#createURLStreamHandler(String)` returns a singleton object per protocol.

Prototype design patterns are also evident in the Java API, for example, in `#clone()` methods, which return a copy of an object with the same properties. This can be seen in various classes throughout the Java SE and Java EE APIs.

Abstract factory design patterns can be observed in Java's factory method implementations, such as `#put()` (which is also present in CharBuffer, ShortBuffer, IntBuffer, LongBuffer, FloatBuffer, and DoubleBuffer).

In addition to these examples, there are many more design patterns that can be found throughout the Java SE and Java EE APIs. These patterns include creational patterns like Singleton, Prototype, Adapter, and Factory.

For a comprehensive overview of various design patterns in software engineering, including those mentioned by GoF (Gang of Four), readers may find it helpful to consult Wikipedia or other reputable sources on the topic.

In conclusion, this article has provided several examples of source code in Java that illustrate various design patterns. These patterns are essential components of software engineering and can be found throughout the Java API.

Example of source code in java