java - 使用 java 8 将 txt 转换为 csv 不适用于大内容

Question

您好，我想将 txt 转换为 CSV 文件。在我的 txt 文件中，我使用\t 作为分隔符。 所以我的java代码如下所示

public static void main(String[] args) throws Exception {
        final Path path = Paths.get("D:\\chat-log\\output\\");
        final Path txt = path.resolve("summary_Traders_Violation_Rule2_Conversation.txt");
        final Path csv = path.resolve("Rule2.csv");
        try (
                final Stream<String> lines = Files.lines(txt);
                final PrintWriter pw = new PrintWriter(Files.newBufferedWriter(csv, StandardOpenOption.CREATE_NEW))) {
            lines.map((line) -> line.split("\t")).
                    map((line) -> Stream.of(line).collect(Collectors.joining(","))).
                    forEach(pw::println);
        }
    } 

它创建 CSV 文件时出现异常，并且 csv 文件不包含 txt 文件中的完整数据。在第 4 列值开始抛出异常时，直到第 1、2、3 列之前只有空白值是可以的。

Exception in thread "main" java.io.UncheckedIOException: java.nio.charset.MalformedInputException: Input length = 1
    at java.io.BufferedReader$1.hasNext(Unknown Source)
    at java.util.Iterator.forEachRemaining(Unknown Source)
    at java.util.Spliterators$IteratorSpliterator.forEachRemaining(Unknown Source)
    at java.util.stream.AbstractPipeline.copyInto(Unknown Source)
    at java.util.stream.AbstractPipeline.wrapAndCopyInto(Unknown Source)
    at java.util.stream.ForEachOps$ForEachOp.evaluateSequential(Unknown Source)
    at java.util.stream.ForEachOps$ForEachOp$OfRef.evaluateSequential(Unknown Source)
    at java.util.stream.AbstractPipeline.evaluate(Unknown Source)
    at java.util.stream.ReferencePipeline.forEach(Unknown Source)
    at XPathEx.TxtToCsv.main(TxtToCsv.java:24)
Caused by: java.nio.charset.MalformedInputException: Input length = 1
    at java.nio.charset.CoderResult.throwException(Unknown Source)
    at sun.nio.cs.StreamDecoder.implRead(Unknown Source)
    at sun.nio.cs.StreamDecoder.read(Unknown Source)
    at java.io.InputStreamReader.read(Unknown Source)
    at java.io.BufferedReader.fill(Unknown Source)
    at java.io.BufferedReader.readLine(Unknown Source)
    at java.io.BufferedReader.readLine(Unknown Source)
    ... 10 more

Answer 1

Files.lines(Path) 打开文件以 UTF-8 作为字符集进行读取，并且您的文件似乎包含一些非 UTF-8 数据。

检查您需要哪个字符集，然后使用Files.lines(Path path, Charset cs)相反。