# Replace Map::get by Map::getOrDefault
# Description
Java 8 introduced Map::getOrDefault (opens new window) which offers the possibility to return a default value if the map does not contain a mapping for the given key.
This rule replaces the invocations of Map::get followed by a null-check with Map::getOrDefault.
# Benefits
Makes the code more readable, by using Java 8 extensions of Map interface.
# Tags
# Code Changes
Pre
String value = concurrentHashMap.get(key);
if(value == null) {
value = defaultValue;
}
Post
String value = concurrentHashMap.getOrDefault(key, defaultValue);
# Limitations
The rule applies only on map implementations that do not allow null values, namely:
Attributes(opens new window)ConcurrentHashMap(opens new window)ConcurrentSkipListMap(opens new window)Hashtable(opens new window)Properties(opens new window).
Use a Java Refactoring Tool
No license required
You can review this refactoring on your code without a license by installing jSparrow to your Eclipse IDE. Install the plug-in from Eclipse IDE: Eclipse Marketplace.
System-wide Refactoring
Do you want to automate this refactoring (and many more) to your system-wide code? The automatic application of this system-wide refactoring can be unlocked by acquiring your jSparrow license.
# Properties
| Property | Value |
|---|---|
| Rule ID | MapGetOrDefault |
| First seen in jSparrow version | 3.5.0 |
| Minimum Java version | 8 |
| Remediation cost | 2 min |