The Android Support Library Collections framework in the Java Class Library
Android Support Library Collections (Android support library collection) framework is an important part of the Java class library, providing some functions for Android developers.This article will introduce the characteristics and use of the framework in detail, and at the same time it will provide some Java code examples to help readers better understand.
Android Support Library Collection's framework is composed of a series of categories and is used to operate and manage collection objects.Some of these core categories include ArraySet, ArrayMap, Sparsearray and so on.
1. ArraySet
ArraySet is a collection class used to store unique values, similar to SET interfaces.It uses an array to store elements and does not allow repetition values.Its main characteristics are:
-Frocked quickly: ArraySet uses a two -point search algorithm to quickly determine whether the element exists.
-Datalog optimization: Compared to using HashMap or HashSet, ArraySet occupied less memory, especially when there are fewer storage objects.
The following is a simple example of ArraySet:
ArraySet<String> fruits = new ArraySet<>();
fruits.add("apple");
fruits.add("banana");
fruits.add("orange");
if (fruits.contains("banana")) {
fruits.remove("banana");
}
for (String fruit : fruits) {
System.out.println(fruit);
}
2. ArrayMap
ArrayMap is a key value -to -storage structure similar to the MAP interface.Compared with HashMap, ArrayMap can provide higher performance and memory efficiency when storing a small amount of key values.The main features include:
-Afurate: ArrayMap uses a two -point search algorithm to find and access key value pairs.
-Datalog optimization: Compared to HashMap, ArrayMap occupies less memory when there are fewer storage objects.
The following is an example code of ArrayMap:
ArrayMap<String, Integer> scores = new ArrayMap<>();
scores.put("John", 90);
scores.put("Sarah", 85);
scores.put("Mike", 95);
int johnsScore = scores.get("John");
scores.remove("Sarah");
for (int i = 0; i < scores.size(); i++) {
String name = scores.keyAt(i);
int score = scores.valueAt(i);
System.out.println(name + ": " + score);
}
3. SparseArray
Sparsearray is a sparse array class that is optimized for Android.It provides more efficient memory use and query performance than ordinary Java arrays.Sparsearray is suitable for a small and discontinuous situation. The main features include:
-Datalog optimization: Compared to using HashMap, Sparsearray occupies less memory when storing the integer key value pairs.
-Procate: Sparsearray uses a two -point search algorithm for key value -paired search.
The following is the example code of Sparsearray:
SparseArray<String> messageMap = new SparseArray<>();
messageMap.put(0, "Hello");
messageMap.put(5, "World");
messageMap.put(10, "!");
String message = messageMap.get(5);
messageMap.delete(0);
for (int i = 0; i < messageMap.size(); i++) {
int key = messageMap.keyAt(i);
String value = messageMap.valueAt(i);
System.out.println(key + ": " + value);
}
Summarize:
The Android SUPPORT LIBRARY Collections framework provides arraySet, ArrayMap and Sparsearray, which facilitates the operation and management of the collection of Android developers.By using these collection classes, data can be processed and stored more efficiently.It is hoped that the instructions and example code of this article can help readers understand and use these functions.
