Should use Map instead of Hashtable

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Metadata

ID: java-best-practices/replace-hashtable-with-map

Language: Java

Severity: Warning

Category: Best Practices

Description

If your application does not require thread safety, it is recommended to use the modern java.util.Map interface instead of java.util.Hashtable.

Map offers efficient implementations like HashMap, which offer greater flexibility and faster execution. If thread safety is needed, you can opt for ConcurrentHashMap, which maintains thread safety while still adhering to modern coding practices associated with Map.

Non-Compliant Code Examples

public class Foo {
    void bar() {
        Hashtable hashtable1 = new Hashtable(); // consider using java.util.Map instead
        Hashtable<String, Integer> hashtable2 = new Hashtable<>();
    }
}

Compliant Code Examples

public class Foo {
    void bar() {
        Map<String, Integer> h = new HashMap<>();
    }
}