如何用 ArrayList 中的元素替換字符串變量中的單個單詞？

Question

ArrayList<String> nounsList = new ArrayList<String>();
ArrayList<String> verbsList = new ArrayList<String>();

（數組列表是從兩個文件的內容創建的）

while((line_2 = wordReader2.readLine()) != null){
  //save all words in nouns.txt to array
  nounsList.add(line_2);
}

while((line_3 = wordReader3.readLine()) != null){
  //save all words in verbs.txt to array
  verbsList.add(line_3);
}

String libStory = "A paragraph is a series of related sentences developing a central idea, called the topic. Try to think about paragraphs in terms of thematic unity: a paragraph is a sentence or a group of sentences that supports one central, unified idea. Paragraphs add one idea at a time to your broader argument";

Random rand = new Random(); //required to pick random noun in nounsList array
int randElement;

    for (int y = 0; y < libStory.length(); y++) {
  
      randElement = rand.nextInt(nounsList.size());

      libStory.replace("paragraph", nounsList.get(randElement)); 
 

  }//end of for loop

它顯示了一個錯誤（不兼容的類型：int 無法轉換為 String）。

我想做什么：我想從我的字符串變量（libStory）中 select 一個特定的詞（段落），並用另一個詞替換它，該詞是我的 arrayList（名詞列表）中的一個元素。 任何建議如何實現這一目標？ 或者如何修復我的代碼來實現這一點？ 先感謝您。

編輯：如果我有一個字符串怎么辦（“A % 是一系列相關的句子，形成一個中心 %，稱為 %。嘗試從主題統一性的角度考慮段落：一個段落是一個 % 或一組 % 支持一個中心、統一的想法”），並且每次出現另一個 % 時，我想用數組中的不同元素替換占位符 (%)？

Answer 1

如果您的目標是用列表中的一個隨機元素替換"paragraph"的每個精度，則不需要使用 for 循環。 String.replace(CharSequence target, CharSequence replacement)將為您完成。 來自 java 文檔：

用指定的文字替換序列替換此字符串中與文字目標序列匹配的每個 substring。

    ArrayList<String> nounsList = ...

    String libStory = "A paragraph is a series of related ...";
    
    Random rand = new Random();
    
    libStory = libStory.replace("paragraph", nounsList.get(rand.nextInt(nounsList.size())));

    System.out.println(libStory);

只是不要忘記將替換的字符串分配給您的原始字符串，即

libStory = libStory.replace("paragraph",...

Answer 2

根據描述和評論，要將所有出現的“段落”替換為隨機名詞，您可以使用replace() ：

List<String> nounsList = Arrays.asList("paragraph", "series", "sentences");
String libStory = "A paragraph is a series of related sentences developing a central idea, called the topic. Try to think about paragraphs in terms of thematic unity: a paragraph is a sentence or a group of sentences that supports one central, unified idea. Paragraphs add one idea at a time to your broader argument";

Random rand = new Random(); //required to pick random noun in nounsList array

int randElementIndex = rand.nextInt(nounsList.size());
libStory = libStory.replace("paragraph", nounsList.get(randElementIndex));

System.out.println(libStory);

Output：

A series is a series of related sentences developing a central idea, called the topic. Try to think about seriess in terms of thematic unity: a series is a sentence or a group of sentences that supports one central, unified idea. Paragraphs add one idea at a time to your broader argument