如何替换字符串消息中的单词？
How to replace a word in string message?
我在这方面已经有一段时间尝试了一些不同的代码。当我尝试替换单词时说我的替换代码是错误的。我怎样才能替换消息中的所有单词？
public class StorySynthesiser {
public static void main(String[] args) {
String message;
String name ="Tiger";
String result = message.replaceAll("Hare", name);
message = "";
message = message +"There once was a speedy Hare who bragged about how fast he could run.\n";
message = message +"Tired of hearing him boast, the Tortoise challenged him to a race.\n";
message = message +"All the animals in the forest gathered to watch.\n";
message = message +"The Hare ran down the road for a while and then paused to rest. \n";
message = message +"He looked back at the tortoise and cried out, \"How do you expect to win this race when you are walking along at your slow, slow pace?\n";
message = message +"The Tortoise walked and walked, never ever stopping until he came to the finish line.\n";
message = message +"The animals who were watching cheered so loudly for Tortoise that they woke up the Hare. The Hare stretched, yawned and began to run again, but it was too late.\n";
message = message +"Tortoise had already crossed the finish line in 2 hours ago/n";
JOptionPane.showMessageDialog(null, message);
您需要在您实际为邮件分配内容后进行替换：
String message = "content here...";
String result = message.replaceAll("Hare", name);
请注意，由于您实际上并没有进行正则表达式替换，因此您不妨在此处使用 String#replace 以获得更好的性能：
String result = message.replace("Hare", name);
您要先替换，然后再赋值，还要在您的 DialogPane 中显示另一个变量，因此您需要这样做：
String name ="Tiger";
message = "";
message = message +"There once was a speedy Hare who bragged about how fast he could run.\n";
message = message +"Tired of hearing him boast, the Tortoise challenged him to a race.\n";
message = message +"All the animals in the forest gathered to watch.\n";
message = message +"The Hare ran down the road for a while and then paused to rest. \n";
message = message +"He looked back at the tortoise and cried out, \"How do you expect to win this race when you are walking along at your slow, slow pace?\n";
message = message +"The Tortoise walked and walked, never ever stopping until he came to the finish line.\n";
message = message +"The animals who were watching cheered so loudly for Tortoise that they woke up the Hare. The Hare stretched, yawned and began to run again, but it was too late.\n";
message = message +"Tortoise had already crossed the finish line in 2 hours ago/n";
String result = message.replaceAll("Hare", name);
JOptionPane.showMessageDialog(null, result);
您需要在此处更改两件事
初始化变量
String message;
并在末尾调用替换，如下所示。
String message = "";
String name ="Tiger";
message = message +"There once was a speedy Hare who bragged about how fast he could run.\n";
message = message +"Tired of hearing him boast, the Tortoise challenged him to a race.\n";
message = message +"All the animals in the forest gathered to watch.\n";
message = message +"The Hare ran down the road for a while and then paused to rest. \n";
message = message +"He looked back at the tortoise and cried out, \"How do you expect to win this race when you are walking along at your slow, slow pace?\n";
message = message +"The Tortoise walked and walked, never ever stopping until he came to the finish line.\n";
message = message +"The animals who were watching cheered so loudly for Tortoise that they woke up the Hare. The Hare stretched, yawned and began to run again, but it was too late.\n";
message = message +"Tortoise had already crossed the finish line in 2 hours ago/n";
String result = message.replaceAll("Hare", name);
JOptionPane.showMessageDialog(null, message);
您必须在声明期间初始化您的 message 变量，因为它是所有同步的，您必须在追加 message 变量后放置 replaceAll ，否则您将得到一个空的字符串.
public class StorySynthesiser {
public static void main(String[] args) {
String message=""; // initailize your message here
String name ="Tiger";
message = message +"There once was a speedy Hare who bragged about how fast he could run.\n";
message = message +"Tired of hearing him boast, the Tortoise challenged him to a race.\n";
message = message +"All the animals in the forest gathered to watch.\n";
message = message +"The Hare ran down the road for a while and then paused to rest. \n";
message = message +"He looked back at the tortoise and cried out, \"How do you expect to win this race when you are walking along at your slow, slow pace?\n";
message = message +"The Tortoise walked and walked, never ever stopping until he came to the finish line.\n";
message = message +"The animals who were watching cheered so loudly for Tortoise that they woke up the Hare. The Hare stretched, yawned and began to run again, but it was too late.\n";
message = message +"Tortoise had already crossed the finish line in 2 hours ago/n";
String result = message.replaceAll("Hare", name);
System.out.println(result);
}}
工作repl
在此代码中，当您调用replaceAll 时，消息为空。
你必须在分配后调用它。
String message = "";
String name ="Tiger";
message += "There once was a speedy Hare who bragged about how fast he could run.\n";
message += "Tired of hearing him boast, the Tortoise challenged him to a race.\n";
message += "All the animals in the forest gathered to watch.\n";
message += "The Hare ran down the road for a while and then paused to rest. \n";
message += "He looked back at the tortoise and cried out, \"How do you expect to win this race when you are walking along at your slow, slow pace?\n";
message += "The Tortoise walked and walked, never ever stopping until he came to the finish line.\n";
message += "The animals who were watching cheered so loudly for Tortoise that they woke up the Hare. The Hare stretched, yawned and began to run again, but it was too late.\n";
message += "Tortoise had already crossed the finish line in 2 hours ago/n";
String result = message.replaceAll("Hare", name);
JOptionPane.showMessageDialog(null, result);
您正在 替换字符串，然后 设置消息。考虑更改顺序：
String message; //message is now null, trying to replace will cause a Null pointer exception.
String name ="Tiger";
message = ""; //message is now an empty string, replaceing something will be useless as there is nothing there.
message = message +"There once was a speedy Hare who bragged about how fast he could run.\n";
message = message +"Tired of hearing him boast, the Tortoise challenged him to a race.\n";
message = message +"All the animals in the forest gathered to watch.\n";
message = message +"The Hare ran down the road for a while and then paused to rest. \n";
message = message +"He looked back at the tortoise and cried out, \"How do you expect to win this race when you are walking along at your slow, slow pace?\n";
message = message +"The Tortoise walked and walked, never ever stopping until he came to the finish line.\n";
message = message +"The animals who were watching cheered so loudly for Tortoise that they woke up the Hare. The Hare stretched, yawned and began to run again, but it was too late.\n";
message = message +"Tortoise had already crossed the finish line in 2 hours ago/n";
//here message is full and has some "Hare" to replace.
String result = message.replaceAll("Hare", name);
JOptionPane.showMessageDialog(null, message);
检查此 off-topic 提示：
message = message + "hello";
等同于：
message += "hello";
我在这方面已经有一段时间尝试了一些不同的代码。当我尝试替换单词时说我的替换代码是错误的。我怎样才能替换消息中的所有单词？
public class StorySynthesiser {
public static void main(String[] args) {
String message;
String name ="Tiger";
String result = message.replaceAll("Hare", name);
message = "";
message = message +"There once was a speedy Hare who bragged about how fast he could run.\n";
message = message +"Tired of hearing him boast, the Tortoise challenged him to a race.\n";
message = message +"All the animals in the forest gathered to watch.\n";
message = message +"The Hare ran down the road for a while and then paused to rest. \n";
message = message +"He looked back at the tortoise and cried out, \"How do you expect to win this race when you are walking along at your slow, slow pace?\n";
message = message +"The Tortoise walked and walked, never ever stopping until he came to the finish line.\n";
message = message +"The animals who were watching cheered so loudly for Tortoise that they woke up the Hare. The Hare stretched, yawned and began to run again, but it was too late.\n";
message = message +"Tortoise had already crossed the finish line in 2 hours ago/n";
JOptionPane.showMessageDialog(null, message);
您需要在您实际为邮件分配内容后进行替换：
String message = "content here...";
String result = message.replaceAll("Hare", name);
请注意，由于您实际上并没有进行正则表达式替换，因此您不妨在此处使用 String#replace 以获得更好的性能：
String result = message.replace("Hare", name);
您要先替换，然后再赋值，还要在您的 DialogPane 中显示另一个变量，因此您需要这样做：
String name ="Tiger";
message = "";
message = message +"There once was a speedy Hare who bragged about how fast he could run.\n";
message = message +"Tired of hearing him boast, the Tortoise challenged him to a race.\n";
message = message +"All the animals in the forest gathered to watch.\n";
message = message +"The Hare ran down the road for a while and then paused to rest. \n";
message = message +"He looked back at the tortoise and cried out, \"How do you expect to win this race when you are walking along at your slow, slow pace?\n";
message = message +"The Tortoise walked and walked, never ever stopping until he came to the finish line.\n";
message = message +"The animals who were watching cheered so loudly for Tortoise that they woke up the Hare. The Hare stretched, yawned and began to run again, but it was too late.\n";
message = message +"Tortoise had already crossed the finish line in 2 hours ago/n";
String result = message.replaceAll("Hare", name);
JOptionPane.showMessageDialog(null, result);
您需要在此处更改两件事
初始化变量
String message;
并在末尾调用替换，如下所示。
String message = "";
String name ="Tiger";
message = message +"There once was a speedy Hare who bragged about how fast he could run.\n";
message = message +"Tired of hearing him boast, the Tortoise challenged him to a race.\n";
message = message +"All the animals in the forest gathered to watch.\n";
message = message +"The Hare ran down the road for a while and then paused to rest. \n";
message = message +"He looked back at the tortoise and cried out, \"How do you expect to win this race when you are walking along at your slow, slow pace?\n";
message = message +"The Tortoise walked and walked, never ever stopping until he came to the finish line.\n";
message = message +"The animals who were watching cheered so loudly for Tortoise that they woke up the Hare. The Hare stretched, yawned and began to run again, but it was too late.\n";
message = message +"Tortoise had already crossed the finish line in 2 hours ago/n";
String result = message.replaceAll("Hare", name);
JOptionPane.showMessageDialog(null, message);
您必须在声明期间初始化您的 message 变量，因为它是所有同步的，您必须在追加 message 变量后放置 replaceAll ，否则您将得到一个空的字符串.
public class StorySynthesiser {
public static void main(String[] args) {
String message=""; // initailize your message here
String name ="Tiger";
message = message +"There once was a speedy Hare who bragged about how fast he could run.\n";
message = message +"Tired of hearing him boast, the Tortoise challenged him to a race.\n";
message = message +"All the animals in the forest gathered to watch.\n";
message = message +"The Hare ran down the road for a while and then paused to rest. \n";
message = message +"He looked back at the tortoise and cried out, \"How do you expect to win this race when you are walking along at your slow, slow pace?\n";
message = message +"The Tortoise walked and walked, never ever stopping until he came to the finish line.\n";
message = message +"The animals who were watching cheered so loudly for Tortoise that they woke up the Hare. The Hare stretched, yawned and began to run again, but it was too late.\n";
message = message +"Tortoise had already crossed the finish line in 2 hours ago/n";
String result = message.replaceAll("Hare", name);
System.out.println(result);
}}
工作repl
在此代码中，当您调用replaceAll 时，消息为空。 你必须在分配后调用它。
String message = "";
String name ="Tiger";
message += "There once was a speedy Hare who bragged about how fast he could run.\n";
message += "Tired of hearing him boast, the Tortoise challenged him to a race.\n";
message += "All the animals in the forest gathered to watch.\n";
message += "The Hare ran down the road for a while and then paused to rest. \n";
message += "He looked back at the tortoise and cried out, \"How do you expect to win this race when you are walking along at your slow, slow pace?\n";
message += "The Tortoise walked and walked, never ever stopping until he came to the finish line.\n";
message += "The animals who were watching cheered so loudly for Tortoise that they woke up the Hare. The Hare stretched, yawned and began to run again, but it was too late.\n";
message += "Tortoise had already crossed the finish line in 2 hours ago/n";
String result = message.replaceAll("Hare", name);
JOptionPane.showMessageDialog(null, result);
您正在 替换字符串，然后 设置消息。考虑更改顺序：
String message; //message is now null, trying to replace will cause a Null pointer exception.
String name ="Tiger";
message = ""; //message is now an empty string, replaceing something will be useless as there is nothing there.
message = message +"There once was a speedy Hare who bragged about how fast he could run.\n";
message = message +"Tired of hearing him boast, the Tortoise challenged him to a race.\n";
message = message +"All the animals in the forest gathered to watch.\n";
message = message +"The Hare ran down the road for a while and then paused to rest. \n";
message = message +"He looked back at the tortoise and cried out, \"How do you expect to win this race when you are walking along at your slow, slow pace?\n";
message = message +"The Tortoise walked and walked, never ever stopping until he came to the finish line.\n";
message = message +"The animals who were watching cheered so loudly for Tortoise that they woke up the Hare. The Hare stretched, yawned and began to run again, but it was too late.\n";
message = message +"Tortoise had already crossed the finish line in 2 hours ago/n";
//here message is full and has some "Hare" to replace.
String result = message.replaceAll("Hare", name);
JOptionPane.showMessageDialog(null, message);
检查此 off-topic 提示：
message = message + "hello";
等同于：
message += "hello";