替换字符串中的字符，而不使用字符串replace()方法[关闭]

我有一个字符串，String originalString= "This car is my car";
我想用“自行车”替换“汽车”，而不使用字符串replace() method.

class StringTest{
   public static void main(String[] args){
      String originalString = "This car is my car";
      String replacedString = replaceMethod(original, "car", "bike");
      System.out.println(replacedString);
   }  
}
static String replaceMethod( String original, String toReplace, String replacedWith){
    // enter code here
    return "";
}

您可以拆分“汽车”，然后添加“自行车”连接

import java.util.*;

class StringTest 
{
    public static void main(String[] args)
    {
        String originalString = "This car is my car";
        String replacedString = replaceMethod(originalString, "car", "bike");
        System.out.println(replacedString);
    }

    static String replaceMethod(String str, String from, String to) 
    {
        String[] arr = str.split(from);
        StringBuilder output = new StringBuilder();

        int i = 0;
        for (; i < arr.length - 1; i++)
        output.append(arr[i]).append(to);

        output.append(arr[i]);
        if (str.substring(str.lastIndexOf(" ")).equalsIgnoreCase(" " + from))
            output.append(to);

        return output.toString();
    }
}

原始字符串

This car is my car

output

This bike is my bike

感谢 Polywhirl 先生的帮助。