Given the code fragments: ``java public class Product { String name; Integer price; Product(String name, Integer price) { this.name = name; this.price = price; } public void printVal() {…

Question

public class Product {
 String name;
 Integer price;
 Product(String name, Integer price) {
 this.name = name;
 this.price = price;
 }
 public void printVal() { System.out.print(name + " Price:" + price + " "); }
 public void setPrice(int price) { this.price = price; }
 public Integer getPrice() { return price; }
}

List<Product> li = Arrays.asList(new Product("TV", 1000), new Product("Refrigerator", 2000));
Consumer<Product> raise = e -> e.setPrice(e.getPrice() + 100);
li.forEach(raise);
li.forEach(Product::printVal);

Options

• ATV Price :110 Refrigerator Price :2100
• BA compilation error occurs.
• CTV Price :1000 Refrigerator Price :2000
• DThe program prints nothing.

• A
  78% (18)
• B
  4% (1)
• C
  9% (2)
• D
  9% (2)

Explanation

Option A is correct because the Consumer<Product> raise lambda mutates each product's price in-place by calling setPrice(getPrice() + 100) - making TV 1100 and Refrigerator 2100 - and since forEach(raise) executes before forEach(Product::printVal), the updated prices are what get printed. (Note: "TV Price:110" in option A appears to be a typo for "TV Price:1100.")

Why the distractors are wrong:

• B (compilation error): The code is valid - Consumer<Product> is a proper functional interface, Arrays.asList(...) returns a List<Product>, and Product::printVal is a legal instance method reference.
• C (original prices): This would be correct only if forEach(raise) were never called, but it is called first, so prices are already updated when printVal runs.
• D (prints nothing): printVal explicitly calls System.out.print(...), so output is always produced.

Memory tip: Think of Consumer<T> as a "side-effect machine" - it takes an object and changes it without returning anything. When you see forEach(consumer) followed by forEach(printer), the first pass mutates, the second pass reads the mutated state.

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