java - 使用java 8从文件中读取数据 block

Question

我需要使用 java 8 读取文本文件。我可以读取整个文件。但我的问题是如何只读取文件的一部分。

例子:我需要读取 {AAAA} {/AAAA} 之间的数据。我如何使用 Java 8 及更早版本执行此操作？

{AAAA}
This is the detailed description. This needs to be printed in the book
{/AAAA}
{BBBB}
Sample Code 1
Sample Code 2
Sample Code 3
{/BBBB}

Answer 1

你能做的最好的事情就是逐行阅读你的文件，直到你通过做类似的事情达到你的模式:

try (BufferedReader br = new BufferedReader(
     new InputStreamReader(new File(file), charset))
 ) {
    String line;
    boolean start = false;
    // Read the file line by line
    while ((line = br.readLine()) != null) {
        if (start) {
            // Here the start pattern has been found already
            if (line.equals("{/AAAA}")) {
                // The end pattern has been reached so we stop reading the file
                break;
            }
            // The line is not the end pattern so we treat it
            doSomething(line);
        } else {
            // Here we did not find the start pattern yet
            // so we check if the line is the start pattern
            start = line.equals("{AAAA}");
        }
    }
}

通过这种方式，您只读取文件直到到达结束模式，这比读取整个文件更有效率。