4.0.0 com.iluwatar java-design-patterns 1.0-SNAPSHOT pom UTF-8 abstract-factory builder factory-method prototype singleton adapter bridge composite decorator facade flyweight proxy chain command interpreter iterator mediator memento model-view-presenter observer state strategy template-method visitor double-checked-locking servant service-locator null-object event-aggregator callback execute-around property intercepting-filter poison-pill junit junit 4.11 test org.apache.maven.plugins maven-compiler-plugin 3.0 1.7 1.7