Question

consider the following method that is intended to modify its parameter namelist by replacing all occurrences of name with newvalue.
public void replace(arraylist<string> namelist, string name, string newvalue)
{
for (int j = 0; j < namelist.size(); j++)
{
if ( / expression / )
{
namelist.set(j, newvalue);
}
}
}
which of the following can be used to replace / expression / so that replace will work as intended?
a.
namelist.get(j).equals(name)
b.
namelist.get(j) == name
c.
namelist.remove(j)
d.
namelistj == name

Explanation:

To determine the correct expression, we analyze each option:

• Option A: In Java, to compare the contents of two Strings, we use the equals() method. nameList.get(j).equals(name) checks if the String at index j in nameList has the same content as name, which is correct for replacing occurrences.
• Option B: The == operator in Java compares object references, not the content of Strings. So this would not correctly identify when the String content matches.
• Option C: nameList.remove(j) is a method to remove an element, not to check for a match. This is irrelevant to the condition needed.
• Option D: nameList[j] is not valid syntax for accessing elements in an ArrayList in Java (we use get(j)), and again == is incorrect for String content comparison.

Answer:

A. nameList.get(j).equals(name)