11分钟掌握Java中string和InputStream转换

11分钟掌握Java中string和InputStream转换

相信奇迹的人本身就和奇迹一样了不起啊

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1、InputStream转化为String

1.1 JDK原生提供

方法一：

byte[] bytes = new byte[0];
bytes = new byte[inputStream.available()];
inputStream.read(bytes);
String str = new String(bytes);

方法二：

String result = new BufferedReader(new InputStreamReader(inputStream))
        .lines().collect(Collectors.joining(System.lineSeparator()));

方法三：

String result = new BufferedReader(new InputStreamReader(inputStream))
       .lines().parallel().collect(Collectors.joining(System.lineSeparator()));

方法四：

Scanner s = new Scanner(inputStream).useDelimiter("\\A");
String str = s.hasNext() ? s.next() : "";

方法五：

String resource = new Scanner(inputStream).useDelimiter("\\Z").next();
return resource;

方法六：

StringBuilder sb = new StringBuilder();
String line;

BufferedReader br = new BufferedReader(new InputStreamReader(inputStream));
while ((line = br.readLine()) != null) {
    sb.append(line);
}
String str = sb.toString();
return str;

方法七：

ByteArrayOutputStream result = new ByteArrayOutputStream();
byte[] buffer = new byte[inStream.available()];
int length;
while ((length = inputStream.read(buffer)) != -1) {
    result.write(buffer, 0, length);
}
String str = result.toString(StandardCharsets.UTF_8.name());
return str;

方法八：

BufferedInputStream bis = new BufferedInputStream(inputStream);
ByteArrayOutputStream buf = new ByteArrayOutputStream();
int result = bis.read();
while(result != -1) {
    buf.write((byte) result);
    result = bis.read();
}
String str = buf.toString();
return str;

1.2 Apache Common提供

方法九：

StringWriter writer = new StringWriter();
IOUtils.copy(inputStream, writer, StandardCharsets.UTF_8.name());
String str = writer.toString();

方法十：

String str = IOUtils.toString(inputStream, "utf-8");

1.3 Google Guava提供

方法十一：

String str = CharStreams.toString(new InputStreamReader(inputStream, StandardCharsets.UTF_8));

方法十二：

String str = new String(ByteStreams.toByteArray(inputStream));

2、String转化为InputStream

2.1 JDK原生提供

InputStream is = new ByteArrayInputStream(str.getBytes());

2.2 Apache Common提供

InputStream targetStream = IOUtils.toInputStream(str, StandardCharsets.UTF_8.name());

2.3 Google Guava提供

InputStream targetStream =
        new ReaderInputStream(CharSource.wrap(str).openStream(), StandardCharsets.UTF_8.name());