note

HashMapとMap

HashMap は 「名前とデータをセットにして保存できる箱」 みたいなものだよ。 たとえば、「国」と「首都」をセットで保存する」 ことができる。
GitHub

java.lang.ClassCastException: java.util.HashMap$Node cannot be cast to java.util.HashMap ...

at com.huawei.appmarket.cachesys.datamanager.CacheJSONParser.getUnifyRef(CacheJSONParser.java:703) ~[classes/:?] at com.huawei.appmarket.cachesys.datamanager ...
GitHub

IllegalArgumentException: Can not set final [..].HashMap field [..].IdentificationKeys ...

This issue is split off from #122. The below error occurs both with ZooDB 0.5.2 and 0.6.0. which can be added to our ZooDB database without any issues (of course with ...
ITmedia

Java Tips：Iterator、Enumerationなどループあれこれ：JAVA Developer

java.utilパッケージにはコレクションを表現するクラスが多数あります。配列では要素数が固定になりますから，不定数のオブジェクトを扱うときには便利に使えます。J2SE 5では，Genericsを導入してさらに使いやすく安全になります。 さらに，java.util ...
TheServerSide

How a Java HashMap internal implementation works

A frequently asked question in a Java interview is: How to implement a Java HashMap? Java job seekers must fully grok this important concept if they want to ace the interview. The HashMap tutorial ...
InfoWorld

Java Map.get and Map.containsKey

package dustin.examples; /** * Enum representing select western states in the United Sates. */ public enum States { ARIZONA("Arizona"), CALIFORNIA("California ...
InfoQ

OpenJDK and HashMap …. Safely Teaching an Old Dog New (Off-Heap!) Tricks

A monthly overview of things you need to know as an architect or aspiring architect. Unlock the full InfoQ experience by logging in! Stay updated with your favorite authors and topics, engage with ...