100 Java Mistakes

🚀 com.example.mistakes.expression._13_IncorrectMethodBinding.Ex1

Question fetched from API endpoint api/expression/13/1

API Response

GET /api/expression/13/1

{
  "result": [
    {
      "message": "com.example.mistakes.expression._13_IncorrectMethodBinding.Ex1",
      "before": "    String before(Storage storage) {\n      storage.add(\"users.txt\", \"admin\");\n      storage.add(\"users.txt\", \"guest\");\n      storage.add(\"numbers.txt\", \"3.1415\");\n      return storage.dump();\n    }\n",
      "after": "    String after() {\n      class NewStorage extends Storage {\n        @Override\n        void add(String fileName, String line) {\n          contents.computeIfAbsent(fileName, _ -> new StringBuilder())\n              .append(line).append(\"\\n\");\n        }\n",
      "chapter": 2,
      "id": "2_13_1",
      "className": "Ex1",
      "path": "file:///home/runner/work/100_java_mistakes/100_java_mistakes/back/src/main/java/com/example/mistakes/expression/_13_IncorrectMethodBinding.java"
    }
  ],
  "length": 1
}

before

String before(Storage storage) {
  storage.add("users.txt", "admin");
  storage.add("users.txt", "guest");
  storage.add("numbers.txt", "3.1415");
  return storage.dump();
}

after

String after() {
  class NewStorage extends Storage {
    @Override
    void add(String fileName, String line) {
      contents.computeIfAbsent(fileName, _ -> new StringBuilder())
          .append(line).append("\n");
    }