You won't gain anything by checking that the key exists. This is the code of HashMap:

@Override public boolean containsKey(Object key) { Entry<K, V> m = getEntry(key); return m != null; } @Override public V get(Object key) { Entry<K, V> m = getEntry(key); if (m != null) { return m.value; } return null; } 

Just check if the return value for get() is different from null.

This is the HashMap source code.

Resources :

• HashMap source code

You won't gain anything by checking that the key exists. This is the code of HashMap:

@Override public boolean containsKey(Object key) { Entry<K, V> m = getEntry(key); return m != null; } @Override public V get(Object key) { Entry<K, V> m = getEntry(key); if (m != null) { return m.value; } return null; } 

Just check if the return value for get() is different from null.

This is the HashMap source code.

Resources :

• HashMap source code Bad one
• HashMap source code Good one

You won't gain anything:

@Override public boolean containsKey(Object key) { Entry<K, V> m = getEntry(key); return m != null; } @Override public V get(Object key) { Entry<K, V> m = getEntry(key); if (m != null) { return m.value; } return null; } 

This is the HashMap source code.

Resources :

• HashMap source code

You won't gain anything by checking that the key exists. This is the code of HashMap:

@Override public boolean containsKey(Object key) { Entry<K, V> m = getEntry(key); return m != null; } @Override public V get(Object key) { Entry<K, V> m = getEntry(key); if (m != null) { return m.value; } return null; } 

Just check if the return value for get() is different from null.

This is the HashMap source code.

Resources :

• HashMap source code