Removing Items in a Loop from a List

Learn about several methods to remove items in a loop from a java collection.

“Puns are the highest form of literature.”
― Alfred Hitchcock

1. Introduction

When you have a List or a Set or any other Collection, you may sometimes need to remove items in a loop. For example, you may be maintaining a list of messages for processing, and need to occasionally purge stale items from the list. In such a scenario, you would loop around the collection and remove the stale items.

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Using Java ArrayList’s List Iterator

A ListIterator allows traversal of a Java ArrayList in forward or backward direction.

“A man devoid of hope and conscious of being so has ceased to belong to the future.”
― Albert Camus, The Myth of Sisyphus and Other Essays

1. Introduction

Java’s ArrayList class provides a list iterator which allows, among other things, traversal of the list in either direction. This is in comparison to a normal Iterator that allows traversal of the list in forward direction only. In this article, we delve into the usage and behavior of the ListIterator when used with an ArrayList.

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Searching a List in Java

Easily search a java list using java 8 predicate functions.

“Make improvements, not excuses. Seek respect, not attention.”
― Roy T. Bennett, The Light in the Heart

1. Introduction

Searching, sorting and iterating are some of the fundamental operations required when using a list. Searching refers to finding one or more objects in the list that match a given condition. In this article, we look at some methods for searching a list in java.

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Java ArrayList Benchmark

Learn about ArrayList and LinkedList performance. In this article, we test creation, addition and iteration performance of these containers.

“Don’t mistake activity with achievement.”
― John Wooden

1. Introduction

Let us examine the performance characteristics of List Implementations – ArrayList and LinkedList. We perform the testing for a variety of list sizes from 100 items to 1M items. We use the JMH test harness to conduct the test on a single core machine. Results are presented below.

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