Guava: GOOGLE CORE LIBRARIES for Java's new feature introduction
Guava: GOOGLE CORE LIBRARIES for Java's new feature introduction
GUAVA, that is, Google Core Libraries for Java is a strong core Java library developed by Google.It provides many practical tools and data structures that can simplify the Java development process and improve the readability, maintenance and performance of code.This article will introduce some new features of Guava and provide the corresponding Java code example.
1. Collection tools (Collections)
The GUAVA collection tool provides many powerful and functional collection operation methods, making the operation set easier.The following are examples of the usage of some new collection tools:
(A) Filter (Filter):
List<Integer> numbers = Arrays.asList(1, 2, 3, 4, 5, 6);
List<Integer> evenNumbers = Lists.newArrayList(Collections2.filter(numbers, n -> n % 2 == 0));
System.out.println(evenNumbers); // Output: [2, 4, 6]
(B) Transform:
List<String> names = Arrays.asList("John", "Jane", "Michael");
List<String> upperCaseNames = Lists.newArrayList(Collections2.transform(names, String::toUpperCase));
System.out.println(upperCaseNames); // Output: [JOHN, JANE, MICHAEL]
2. String tool (Strings)
Guava's string tool provides some convenient methods to process and operate string.Here are examples of the usage of some new string tools:
(A) Splitter:
String text = "apple,banana,orange";
List<String> fruits = Lists.newArrayList(Splitter.on(",").split(text));
System.out.println(fruits); // Output: [apple, banana, orange]
(B) Joiner:
List<String> fruits = Arrays.asList("apple", "banana", "orange");
String text = Joiner.on(",").join(fruits);
System.out.println(text); // Output: apple,banana,orange
3. Caches (Caches)
The GUAVA cache tool provides a simple and efficient cache implementation for cache calculation results.The following is an example of using the Guava cache tool:
LoadingCache<String, Integer> cache = CacheBuilder.newBuilder()
.maximumSize(100)
.expireAfterAccess(1, TimeUnit.MINUTES)
.build(new CacheLoader<String, Integer>() {
@Override
public Integer load(String key) {
// Perform some time -consuming calculations and return the result
return computeResult(key);
}
});
Integer result = cache.get("key");
System.out.println(result);
4. Throwables (Throwables)
Guava's abnormal tools provide some methods to simplify abnormal treatment.The following is an example of using the Guava abnormal tool:
try {
// Calling may throw an abnormal method
someMethod();
} catch (Exception e) {
Throwable rootCause = Throwables.getRootCause(e);
System.out.println(rootCause.getMessage());
Throwables.propagateIfInstanceOf(rootCause, IOException.class);
}
The above is some new function introduction of the Guava library and the corresponding Java code example.By using Guava, developers can more conveniently write high -quality Java code.You can access the Guava official website (https://github.com/google/guava) to get more detailed documentation and example code.
