
#### Creational patterns
---

##### Abstract factory

  - <LinkTab href="http://docs.oracle.com/javase/8/docs/api/javax/xml/parsers/DocumentBuilderFactory.html#newInstance--">javax.xml.parsers.DocumentBuilderFactory#newInstance()</LinkTab>
  - <LinkTab href="http://docs.oracle.com/javase/8/docs/api/javax/xml/transform/TransformerFactory.html#newInstance--">javax.xml.transform.TransformerFactory#newInstance()</LinkTab>
  - <LinkTab href="http://docs.oracle.com/javase/8/docs/api/javax/xml/xpath/XPathFactory.html#newInstance--">javax.xml.xpath.XPathFactory#newInstance()</LinkTab>

##### Builder

-   <LinkTab href="http://docs.oracle.com/javase/8/docs/api/java/lang/StringBuilder.html#append-boolean-">java.lang.StringBuilder#append()</LinkTab> (unsynchronized)
-   <LinkTab href="http://docs.oracle.com/javase/8/docs/api/java/lang/StringBuffer.html#append-boolean-">java.lang.StringBuffer#append()</LinkTab> (synchronized)
-   <LinkTab href="http://docs.oracle.com/javase/8/docs/api/java/nio/ByteBuffer.html#put-byte-">java.nio.ByteBuffer#put()</LinkTab> (also on <LinkTab href="http://docs.oracle.com/javase/8/docs/api/java/nio/CharBuffer.html#put-char-">CharBuffer</LinkTab>, <LinkTab href="http://docs.oracle.com/javase/8/docs/api/java/nio/ShortBuffer.html#put-short-">ShortBuffer</LinkTab>, <LinkTab href="http://docs.oracle.com/javase/8/docs/api/java/nio/IntBuffer.html#put-int-">IntBuffer</LinkTab>, <LinkTab href="http://docs.oracle.com/javase/8/docs/api/java/nio/LongBuffer.html#put-long-">LongBuffer</LinkTab>, <LinkTab href="http://docs.oracle.com/javase/8/docs/api/java/nio/FloatBuffer.html#put-float-">FloatBuffer</LinkTab> and <LinkTab href="http://docs.oracle.com/javase/8/docs/api/java/nio/DoubleBuffer.html#put-double-">DoubleBuffer</LinkTab>)
-   <LinkTab href="http://docs.oracle.com/javase/8/docs/api/javax/swing/GroupLayout.Group.html#addComponent-java.awt.Component-">javax.swing.GroupLayout.Group#addComponent()</LinkTab>
-   All implementations of <LinkTab href="http://docs.oracle.com/javase/8/docs/api/java/lang/Appendable.html">java.lang.Appendable</LinkTab>
-   <LinkTab href="https://docs.oracle.com/javase/9/docs/api/java/util/stream/Stream.Builder.html">java.util.stream.Stream.Builder</LinkTab>

##### Factory Method

-   <LinkTab href="http://docs.oracle.com/javase/8/docs/api/java/util/Calendar.html#getInstance--">java.util.Calendar#getInstance()</LinkTab>
-   <LinkTab href="http://docs.oracle.com/javase/8/docs/api/java/util/ResourceBundle.html#getBundle-java.lang.String-">java.util.ResourceBundle#getBundle()</LinkTab>
-   <LinkTab href="http://docs.oracle.com/javase/8/docs/api/java/text/NumberFormat.html#getInstance--">java.text.NumberFormat#getInstance()</LinkTab>
-   <LinkTab href="http://docs.oracle.com/javase/8/docs/api/java/nio/charset/Charset.html#forName-java.lang.String-">java.nio.charset.Charset#forName()</LinkTab>
-   <LinkTab href="http://docs.oracle.com/javase/8/docs/api/java/net/URLStreamHandlerFactory.html">java.net.URLStreamHandlerFactory#createURLStreamHandler(String)</LinkTab> (Returns singleton object per protocol)
-   <LinkTab href="https://docs.oracle.com/javase/8/docs/api/java/util/EnumSet.html#of(E">java.util.EnumSet#of()</LinkTab>)
-   <LinkTab href="https://docs.oracle.com/javase/8/docs/api/javax/xml/bind/JAXBContext.html#createMarshaller--">javax.xml.bind.JAXBContext#createMarshaller()</LinkTab> and other similar methods

##### Prototype

-   <LinkTab href="http://docs.oracle.com/javase/8/docs/api/java/lang/Object.html#clone--">java.lang.Object#clone()</LinkTab> (the class has to implement <LinkTab href="http://docs.oracle.com/javase/8/docs/api/java/lang/Cloneable.html">java.lang.Cloneable</LinkTab>)

##### singleton

-   <LinkTab href="http://docs.oracle.com/javase/8/docs/api/java/lang/Runtime.html#getRuntime--">java.lang.Runtime#getRuntime()</LinkTab>
-   <LinkTab href="http://docs.oracle.com/javase/8/docs/api/java/awt/Desktop.html#getDesktop--">java.awt.Desktop#getDesktop()</LinkTab>
-   <LinkTab href="http://docs.oracle.com/javase/8/docs/api/java/lang/System.html#getSecurityManager--">java.lang.System#getSecurityManager()</LinkTab>

---

#### Structural patterns

---

##### Adapter

-   <LinkTab href="http://docs.oracle.com/javase/17/docs/api/java/util/Arrays.html#asList-T...-">java.util.Arrays#asList()</LinkTab>
-   <LinkTab href="https://docs.oracle.com/javase/8/docs/api/java/util/Collections.html#list-java.util.Enumeration-">java.util.Collections#list()</LinkTab>
-   <LinkTab href="https://docs.oracle.com/javase/8/docs/api/java/util/Collections.html#enumeration-java.util.Collection-">java.util.Collections#enumeration()</LinkTab>
-   <LinkTab href="http://docs.oracle.com/javase/8/docs/api/java/io/InputStreamReader.html#InputStreamReader-java.io.InputStream-">java.io.InputStreamReader(InputStream)</LinkTab> (returns a `Reader`)
-   <LinkTab href="http://docs.oracle.com/javase/8/docs/api/java/io/OutputStreamWriter.html#OutputStreamWriter-java.io.OutputStream-">java.io.OutputStreamWriter(OutputStream)</LinkTab> (returns a `Writer`)
-   <LinkTab href="http://docs.oracle.com/javase/8/docs/api/javax/xml/bind/annotation/adapters/XmlAdapter.html#marshal-BoundType-">javax.xml.bind.annotation.adapters.XmlAdapter#marshal()</LinkTab> and <LinkTab href="http://docs.oracle.com/javase/8/docs/api/javax/xml/bind/annotation/adapters/XmlAdapter.html#unmarshal-ValueType-">#unmarshal()</LinkTab>

##### Bridge

-   None comes to mind yet. A fictive example would be `new LinkedHashMap(LinkedHashSet<K>, List<V>)` which returns an unmodifiable linked map which doesn't clone the items, but *uses* them. The <LinkTab href="http://docs.oracle.com/javase/8/docs/api/java/util/Collections.html#newSetFromMap-java.util.Map-">java.util.Collections#newSetFromMap()</LinkTab> and <LinkTab href="http://docs.oracle.com/javase/8/docs/api/java/util/Collections.html#singleton-T-">singletonXXX()</LinkTab> methods however comes close.

##### Composite

-   <LinkTab href="http://docs.oracle.com/javase/8/docs/api/java/awt/Container.html#add-java.awt.Component-">java.awt.Container#add(Component)</LinkTab> (practically all over Swing thus)
-   <LinkTab href="http://docs.oracle.com/javaee/7/api/javax/faces/component/UIComponent.html#getChildren--">javax.faces.component.UIComponent#getChildren()</LinkTab> (practically all over JSF UI thus)

##### Decorator

-   All subclasses of <LinkTab href="http://docs.oracle.com/javase/8/docs/api/java/io/InputStream.html">java.io.InputStream</LinkTab>, <LinkTab href="http://docs.oracle.com/javase/8/docs/api/java/io/OutputStream.html">OutputStream</LinkTab>, <LinkTab href="http://docs.oracle.com/javase/8/docs/api/java/io/Reader.html">Reader</LinkTab> and <LinkTab href="http://docs.oracle.com/javase/8/docs/api/java/io/Writer.html">Writer</LinkTab> have a constructor taking an instance of same type.
-   <LinkTab href="http://docs.oracle.com/javase/8/docs/api/java/util/Collections.html">java.util.Collections</LinkTab>, the <LinkTab href="http://docs.oracle.com/javase/8/docs/api/java/util/Collections.html#checkedCollection-java.util.Collection-java.lang.Class-">checkedXXX()</LinkTab>, <LinkTab href="http://docs.oracle.com/javase/8/docs/api/java/util/Collections.html#synchronizedCollection-java.util.Collection-">synchronizedXXX()</LinkTab> and <LinkTab href="http://docs.oracle.com/javase/8/docs/api/java/util/Collections.html#unmodifiableCollection-java.util.Collection-">unmodifiableXXX()</LinkTab> methods.
-   <LinkTab href="http://docs.oracle.com/javaee/7/api/javax/servlet/http/HttpServletRequestWrapper.html">javax.servlet.http.HttpServletRequestWrapper</LinkTab> and <LinkTab href="http://docs.oracle.com/javaee/7/api/javax/servlet/http/HttpServletResponseWrapper.html">HttpServletResponseWrapper</LinkTab>
-   <LinkTab href="https://docs.oracle.com/javase/7/docs/api/javax/swing/JScrollPane.html">javax.swing.JScrollPane</LinkTab>

##### Facade

-   <LinkTab href="http://docs.oracle.com/javaee/7/api/javax/faces/context/FacesContext.html">javax.faces.context.FacesContext</LinkTab>, it internally uses among others the abstract/interface types <LinkTab href="http://docs.oracle.com/javaee/7/api/javax/faces/lifecycle/Lifecycle.html">LifeCycle</LinkTab>, <LinkTab href="http://docs.oracle.com/javaee/7/api/javax/faces/application/ViewHandler.html">ViewHandler</LinkTab>, <LinkTab href="http://docs.oracle.com/javaee/7/api/javax/faces/application/NavigationHandler.html">NavigationHandler</LinkTab> and many more without that the enduser has to worry about it (which are however overrideable by injection).
-   <LinkTab href="http://docs.oracle.com/javaee/7/api/javax/faces/context/ExternalContext.html">javax.faces.context.ExternalContext</LinkTab>, which internally uses <LinkTab href="http://docs.oracle.com/javaee/7/api/javax/servlet/ServletContext.html">ServletContext</LinkTab>, <LinkTab href="http://docs.oracle.com/javaee/7/api/javax/servlet/http/HttpSession.html">HttpSession</LinkTab>, <LinkTab href="http://docs.oracle.com/javaee/7/api/javax/servlet/http/HttpServletRequest.html">HttpServletRequest</LinkTab>, <LinkTab href="http://docs.oracle.com/javaee/7/api/javax/servlet/http/HttpServletResponse.html">HttpServletResponse</LinkTab>, etc.

##### Flyweight

-   <LinkTab href="http://docs.oracle.com/javase/8/docs/api/java/lang/Integer.html#valueOf-int-">java.lang.Integer#valueOf(int)</LinkTab> (also on <LinkTab href="http://docs.oracle.com/javase/8/docs/api/java/lang/Boolean.html#valueOf-boolean-">Boolean</LinkTab>, <LinkTab href="http://docs.oracle.com/javase/8/docs/api/java/lang/Byte.html#valueOf-byte-">Byte</LinkTab>, <LinkTab href="http://docs.oracle.com/javase/8/docs/api/java/lang/Character.html#valueOf-char-">Character</LinkTab>, <LinkTab href="http://docs.oracle.com/javase/8/docs/api/java/lang/Short.html#valueOf-short-">Short</LinkTab>, <LinkTab href="http://docs.oracle.com/javase/8/docs/api/java/lang/Long.html#valueOf-long-">Long</LinkTab> and <LinkTab href="https://docs.oracle.com/javase/8/docs/api/java/math/BigDecimal.html#valueOf-long-int-">BigDecimal</LinkTab>)

##### Proxy

-   <LinkTab href="http://docs.oracle.com/javase/8/docs/api/java/lang/reflect/Proxy.html">java.lang.reflect.Proxy</LinkTab>
-   <LinkTab href="http://docs.oracle.com/javase/8/docs/api/java/rmi/package-summary.html">java.rmi.*</LinkTab>
-   <LinkTab href="http://docs.oracle.com/javaee/7/api/javax/ejb/EJB.html">javax.ejb.EJB</LinkTab> ([explanation here](https://stackoverflow.com/questions/25514361/when-using-ejb-does-each-managed-bean-get-its-own-ejb-instance))
-   <LinkTab href="http://docs.oracle.com/javaee/7/api/javax/inject/Inject.html">javax.inject.Inject</LinkTab> ([explanation here](https://stackoverflow.com/questions/29651008/field-getobj-returns-all-nulls-on-injected-cdi-managed-beans-while-manually-i/29672591#29672591))
-   <LinkTab href="http://docs.oracle.com/javaee/7/api/javax/persistence/PersistenceContext.html">javax.persistence.PersistenceContext</LinkTab>

---

#### Behavioral patterns

---

##### Chain of responsibility

-   <LinkTab href="http://docs.oracle.com/javase/8/docs/api/java/util/logging/Logger.html#log-java.util.logging.Level-java.lang.String-">java.util.logging.Logger#log()</LinkTab>
-   <LinkTab href="http://docs.oracle.com/javaee/7/api/javax/servlet/Filter.html#doFilter-javax.servlet.ServletRequest-javax.servlet.ServletResponse-javax.servlet.FilterChain-">javax.servlet.Filter#doFilter()</LinkTab>

##### Command

-   All implementations of <LinkTab href="http://docs.oracle.com/javase/8/docs/api/java/lang/Runnable.html">java.lang.Runnable</LinkTab>
-   All implementations of <LinkTab href="http://docs.oracle.com/javase/8/docs/api/javax/swing/Action.html">javax.swing.Action</LinkTab>

##### Interpreter

-   <LinkTab href="http://docs.oracle.com/javase/8/docs/api/java/util/regex/Pattern.html">java.util.Pattern</LinkTab>
-   <LinkTab href="http://docs.oracle.com/javase/8/docs/api/java/text/Normalizer.html">java.text.Normalizer</LinkTab>
-   All subclasses of <LinkTab href="http://docs.oracle.com/javase/8/docs/api/java/text/Format.html">java.text.Format</LinkTab>
-   All subclasses of <LinkTab href="http://docs.oracle.com/javaee/7/api/javax/el/ELResolver.html">javax.el.ELResolver</LinkTab>

##### Iterator

-   All implementations of <LinkTab href="http://docs.oracle.com/javase/8/docs/api/java/util/Iterator.html">java.util.Iterator</LinkTab> (thus among others also <LinkTab href="http://docs.oracle.com/javase/8/docs/api/java/util/Scanner.html">java.util.Scanner</LinkTab>!).
-   All implementations of <LinkTab href="http://docs.oracle.com/javase/8/docs/api/java/util/Enumeration.html">java.util.Enumeration</LinkTab>

##### Mediator

-   <LinkTab href="http://docs.oracle.com/javase/8/docs/api/java/util/Timer.html">java.util.Timer</LinkTab> (all `scheduleXXX()` methods)
-   <LinkTab href="http://docs.oracle.com/javase/8/docs/api/java/util/concurrent/Executor.html#execute-java.lang.Runnable-">java.util.concurrent.Executor#execute()</LinkTab>
-   <LinkTab href="http://docs.oracle.com/javase/8/docs/api/java/util/concurrent/ExecutorService.html">java.util.concurrent.ExecutorService</LinkTab> (the `invokeXXX()` and `submit()` methods)
-   <LinkTab href="http://docs.oracle.com/javase/8/docs/api/java/util/concurrent/ScheduledExecutorService.html">java.util.concurrent.ScheduledExecutorService</LinkTab> (all `scheduleXXX()` methods)
-   <LinkTab href="http://docs.oracle.com/javase/8/docs/api/java/lang/reflect/Method.html#invoke-java.lang.Object-java.lang.Object...-">java.lang.reflect.Method#invoke()</LinkTab>

##### Memento

-   <LinkTab href="http://docs.oracle.com/javase/8/docs/api/java/util/Date.html">java.util.Date</LinkTab> (the setter methods do that, `Date` is internally represented by a `long` value)
-   All implementations of <LinkTab href="http://docs.oracle.com/javase/8/docs/api/java/io/Serializable.html">java.io.Serializable</LinkTab>
-   All implementations of <LinkTab href="http://docs.oracle.com/javaee/7/api/javax/faces/component/StateHolder.html">javax.faces.component.StateHolder</LinkTab>

##### Observer

-   <LinkTab href="http://docs.oracle.com/javase/8/docs/api/java/util/Observer.html">java.util.Observer</LinkTab>/<LinkTab href="http://docs.oracle.com/javase/8/docs/api/java/util/Observable.html">java.util.Observable</LinkTab>
-   All implementations of <LinkTab href="http://docs.oracle.com/javase/8/docs/api/java/util/EventListener.html">java.util.EventListener</LinkTab> (e.g. in Swing)
-   <LinkTab href="http://docs.oracle.com/javaee/7/api/javax/servlet/http/HttpSessionBindingListener.html">javax.servlet.http.HttpSessionBindingListener</LinkTab>
-   <LinkTab href="http://docs.oracle.com/javaee/7/api/javax/servlet/http/HttpSessionAttributeListener.html">javax.servlet.http.HttpSessionAttributeListener</LinkTab>
-   <LinkTab href="http://docs.oracle.com/javaee/7/api/javax/faces/event/PhaseListener.html">javax.faces.event.PhaseListener</LinkTab>

##### State

-   <LinkTab href="http://docs.oracle.com/javaee/7/api/javax/faces/lifecycle/Lifecycle.html#execute-javax.faces.context.FacesContext-">javax.faces.lifecycle.LifeCycle#execute()</LinkTab> (controlled by <LinkTab href="http://docs.oracle.com/javaee/7/api/javax/faces/webapp/FacesServlet.html">FacesServlet</LinkTab>, the behaviour is dependent on current phase (state) of JSF lifecycle)

##### Strategy

-   <LinkTab href="http://docs.oracle.com/javase/8/docs/api/java/util/Comparator.html#compare-T-T-">java.util.Comparator#compare()</LinkTab>, e.g. executed by <LinkTab href="https://docs.oracle.com/javase/8/docs/api/java/util/List.html#sort-java.util.Comparator-">List#sort()</LinkTab>.
-   <LinkTab href="http://docs.oracle.com/javaee/7/api/javax/servlet/http/HttpServlet.html">javax.servlet.http.HttpServlet</LinkTab>, the `service()` and all `doXXX()` methods take `HttpServletRequest` and `HttpServletResponse` and the implementor has to process them (and not to get hold of them as instance variables!).
-   <LinkTab href="http://docs.oracle.com/javaee/7/api/javax/servlet/Filter.html#doFilter-javax.servlet.ServletRequest-javax.servlet.ServletResponse-javax.servlet.FilterChain-">javax.servlet.Filter#doFilter()</LinkTab>

##### Template method

-   All non-abstract methods of <LinkTab href="http://docs.oracle.com/javase/8/docs/api/java/io/InputStream.html">java.io.InputStream</LinkTab>, <LinkTab href="http://docs.oracle.com/javase/8/docs/api/java/io/OutputStream.html">java.io.OutputStream</LinkTab>, <LinkTab href="http://docs.oracle.com/javase/8/docs/api/java/io/Reader.html">java.io.Reader</LinkTab> and <LinkTab href="http://docs.oracle.com/javase/8/docs/api/java/io/Writer.html">java.io.Writer</LinkTab>.
-   All non-abstract methods of <LinkTab href="http://docs.oracle.com/javase/8/docs/api/java/util/AbstractList.html">java.util.AbstractList</LinkTab>, <LinkTab href="http://docs.oracle.com/javase/8/docs/api/java/util/AbstractSet.html">java.util.AbstractSet</LinkTab> and <LinkTab href="http://docs.oracle.com/javase/8/docs/api/java/util/AbstractMap.html">java.util.AbstractMap</LinkTab>.
-   <LinkTab href="http://docs.oracle.com/javaee/7/api/javax/servlet/http/HttpServlet.html">javax.servlet.http.HttpServlet</LinkTab>, all the `doXXX()` methods by default sends a HTTP 405 "Method Not Allowed" error to the response. You're free to implement none or any of them.

##### Visitor

-   <LinkTab href="http://docs.oracle.com/javase/8/docs/api/javax/lang/model/element/AnnotationValue.html">javax.lang.model.element.AnnotationValue</LinkTab> and <LinkTab href="http://docs.oracle.com/javase/8/docs/api/javax/lang/model/element/AnnotationValueVisitor.html">AnnotationValueVisitor</LinkTab>
-   <LinkTab href="http://docs.oracle.com/javase/8/docs/api/javax/lang/model/element/Element.html">javax.lang.model.element.Element</LinkTab> and <LinkTab href="http://docs.oracle.com/javase/8/docs/api/javax/lang/model/element/ElementVisitor.html">ElementVisitor</LinkTab>
-   <LinkTab href="http://docs.oracle.com/javase/8/docs/api/javax/lang/model/type/TypeMirror.html">javax.lang.model.type.TypeMirror</LinkTab> and <LinkTab href="http://docs.oracle.com/javase/8/docs/api/javax/lang/model/type/TypeVisitor.html">TypeVisitor</LinkTab>
-   <LinkTab href="http://docs.oracle.com/javase/8/docs/api/java/nio/file/FileVisitor.html">java.nio.file.FileVisitor</LinkTab> and <LinkTab href="http://docs.oracle.com/javase/8/docs/api/java/nio/file/SimpleFileVisitor.html">SimpleFileVisitor</LinkTab>
-   <LinkTab href="http://docs.oracle.com/javaee/7/api/javax/faces/component/visit/VisitContext.html">javax.faces.component.visit.VisitContext</LinkTab> and <LinkTab href="http://docs.oracle.com/javaee/7/api/javax/faces/component/visit/VisitCallback.html">VisitCallback</LinkTab>

Patterns Used In Java