java - 在大字符串中删除字符串模板直到 '\n' - Java

Question

我在使用 Java 中的 String 时遇到问题。我有一个很大的 String，里面有很多 \n 和 \\n。我想删除以特定模板“Chorus:”开头的整行以及该行的其余部分，直到 \n。

我尝试遍历 String 并搜索模板“Chorus:”。当我到达那里时，我连接该行的其余部分，直到到达 \n。然后我使用 myString.reaplaceAll(subString,"") 并得到与开始时相同的 String。

我的代码:

String string = " Police voice:\n"
                        + "Attention all units attention all units\n"
                        + "We have an All Points Bulletin out on a man with green hair\n"
                        + "I repeat we have an APB on a man with green hair\n" 
                        + "He's armed with a knife I repeat he's armed with a knife\n" 
                        + "Proceed with caution watch your back fella's\n"
                        + "He could be coming at your girlfriend next\n\n"

                        + "Verse 1:\n"
                        + "There's a joker on the loose from the psychiatric ward\n" 
                        + "His face is up on the bulletin board with a reward\n"
                        + "He'll stab you with a sword don't be fooled by his charm\n" 
                        + "He's probably armed with intent to do bodily harm\n"
                        + "Ring the alarm, look for a man with green hair\n"
                        + "Check at your girl's house, he was last seen there\n" 
                        + "He's has a mean stare but usually crack's jokes\n"
                        + "Good luck on your mission and guard your backs folks\n\n"

                        + "Chorus:\n"
                        + "I make you think you're a best friend then\n"
                        + "Why I oughtta\n"
                        + "Hit a bitch snake from the back, I make you think you're a best friend then\n"
                        + "Why I oughtta\n"
                        + "Stay away from him he ain't no good!\n\n" 

                        + "Verse 2:\n"
                        + "We got the walkie-talkies to keep us all informed\n"
                        + "Suited up head to toe in detective uniforms\n"
                        + "Our unit storms in, we split the ghetto in sectors\n"
                        + "Locking down every block and put up metal detectors\n"
                        + "Protectors and be sure that you stand close\n"
                        + "Watch each others backs and guard your command post\n"
                        + "And most of all be advised that he's wise\n"
                        + "He could be disguised as one of your very own guys\n\n"

                        + "Chorus:\n"
                        + "I make you think you're a best friend then\n"
                        + "Why I oughtta\n"
                        + "Hit a bitch snake from the back, I make you think you're a best friend then\n" 
                        + "Why I oughtta\n" 
                        + "Stay away from him he ain't no good!\n"

                        + "Verse 3:\n"
                        + "I'm on a solo mission to find him personally\n"
                        + "To settle the score and beat then him mercifully\n" 
                        + "For what he first did to me\n"
                        + "It's sure to be the last\n"
                        + "Following footprints with a magnifying glass\n" 
                        + "To drag his lying ass back to his padded cell\n"
                        + "I'm mad as hell, on the trail of the tattle tail\n" 
                        + "I heard a yell the voice sounded familiar\n"
                        + "Give me your girlfriend or I'm gonna kill ya\n\n" 

                        + "Chorus:\n"
                        + "I make you think you're a best friend then\n" 
                        + "Why I oughtta\n"
                        + "Hit a bitch snake from the back, I make you think you're a best friend then\n"
                        + "Why I oughtta\n"
                        + "Stay away from him he ain't no good!\n\n"

                        + "Verse 4:\n"
                        + "I followed the voice that led down a flight of steps\n"
                        + "Sneezing at dust, and swinging at the spider-webs\n"
                        + "Inside the depths of his basement\n"
                        + "I taste lint in my mouth, then the lights in the place… went!\n"
                        + "I saw my life flash in front of my eyes\n"
                        + "I felt a butcher knife slash at one of my thighs\n"
                        + "None of my guys knew where I'm at I was doomed\n"
                        + "Then I remembered the flashlight in my costume\n\n"

                        + "Chorus: Eminem\n"
                        + "I make you think you're a best friend then\n"
                        + "Why I oughtta\n"
                        + "Hit a bitch snake from the back, I make you think you're a best friend then\n"
                        + "Why I oughtta\n"
                        + "Stay away from him he ain't no good!\n\n"

                        + "Verse 5:\n"
                        + "Dealing with backstabber's there was one thing I learned\n"
                        + "They're only powerful when you got your back turned\n"
                        + "I yearned for the day that we finally met againf\n"
                        + "So I can give him a taste of his own medicine\n"
                        + "He shed his skin, then he promised to come clean\n"
                        + "I took his butcher knife and jabbed it into his spleen\n"
                        + "Cut him at the seam then dragged the fella home\n"
                        + "Beating him over the head with the telephone\n\n"

                        + "Police voice:\n"
                        + "Attention all cars, attention all cars\n"
                        + "Unit 313 has apprehended the suspect\n"
                        + "He's going back to the crazy home, I repeat\n"
                        + "He's going back to the crazy home, how about that?\n\n"

                        + "Chorus:\n"
                        + "I make you think you're a best friend then\n"
                        + "Why I oughtta\n"
                        + "Hit a bitch snake from the back, I make you think you're a best friend then\n"
                        + "Why I oughtta\n"
                        + "Stay away from him he ain't no good!\n"
                        + "I make you think you're a best friend then\n"
                        + "Why I oughtta\n"
                        + "Hit a bitch snake from the back, I make you think you're a best friend then\n"
                        + "Why I oughtta\n"
                        + "Stay away from him he ain't no good!\n"
                        + "I make you think you're a best friend then\n" 
                        + "Why I oughtta\n"
                        + "Hit a bitch snake from the back, I make you think you're a best friend then\n"
                        + "Why I oughtta\n"
                        + "Stay away from him he ain't no good!";

        String subString = ""; // Searching for Chorus: (7 characters) sub sub string in string

        for (int i = 0;i < string.length();i++)
        {
            if (string.charAt(i) == 'C')
            {
                subString = string.substring(i,i + 7);
                subString += " "; // "Chorus: "
                //System.out.println(subString);
                if (subString.equals("Chorus:")) // Delete the row
                {
                    i += 7;
                    while (string.charAt(++i)!= '\n')
                    {
                        //System.out.println(string.charAt(i));
                        subString += string.charAt(i);
                    }
                    string = new String(string.replaceAll(subString, ""));
                }
            }
        }

        printString(string);


    }

    /**
     * 
     * @param string to be printed on the console.
     */
    public static void printString(String string)

我做错了什么？任何帮助将不胜感激。

编辑:为了澄清:将 "abcChorus:def\n"+"gh\n"+"Chorus;ijk\n"+"lmnop" 转换为 "gh\n"+"lmnop"

Answer 1

您应该进入一种语言的基础库，看看它们能做什么，而不是自己推送字符...

    String[] lines = string.split("\n"); // split into array at newlines
    String result = Stream.of(lines)
        .filter(s -> !s.startsWith("Chorus:"))   // filter however you like
        .collect(Collectors.joining("\n"));      // re-join as string with newlines
    System.out.println(result);