Dead store

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In Programming, if we assign a value to a local variable, but the value is not read by any subsequent instruction, then it's called a Dead Store. Generally, tools like FindBugs can report these kind of programming mistakes as warnings.

Java example of a Dead Store:

// DeadStoreExample.java
import java.util.ArrayList;
import java.util.List;
 
public class DeadStoreExample {
 public static void main(String[] args) {
   List<String> list = new ArrayList<String>(); // Dead Store here.
   list = getList();
   System.out.println(list);
 }
 
 private static List<String> getList() {
   // Some intense operation and finally we return a java.util.List
   return new ArrayList<String>();
 }
}

In the above code a List<String> object was created but was never used. Instead, in the next line the reference variable is pointing to some other object in the heap. The object created on line number 6 is never used and hence it's a dead store.