如果您有java.io.InputStream对象,应该如何处理该对象并生成String?
假设我有一个包含文本数据的InputStream,我想将其转换为String,例如,我可以将其写入日志文件。
获取InputStream并将其转换为字符串的最简单方法是什么?
public String convertStreamToString(InputStream is) {
// ???
}
如果您有java.io.InputStream对象,应该如何处理该对象并生成String?
假设我有一个包含文本数据的InputStream,我想将其转换为String,例如,我可以将其写入日志文件。
获取InputStream并将其转换为字符串的最简单方法是什么?
public String convertStreamToString(InputStream is) {
// ???
}
当前回答
使用Streams的纯Java解决方案,从Java8开始工作。
import java.io.BufferedReader;
import java.io.IOException;
import java.io.InputStream;
import java.io.InputStreamReader;
import java.util.stream.Collectors;
// ...
public static String inputStreamToString(InputStream is) throws IOException {
try (BufferedReader br = new BufferedReader(new InputStreamReader(is))) {
return br.lines().collect(Collectors.joining(System.lineSeparator()));
}
}
正如Christoffer Hammarström在其他答案中提到的那样,明确指定Charset更安全。即InputStreamReader构造函数可以按如下方式更改:
new InputStreamReader(is, Charset.forName("UTF-8"))
其他回答
Use:
InputStream in = /* Your InputStream */;
StringBuilder sb = new StringBuilder();
BufferedReader br = new BufferedReader(new InputStreamReader(in));
String read;
while ((read=br.readLine()) != null) {
//System.out.println(read);
sb.append(read);
}
br.close();
return sb.toString();
此代码段位于\sdk\samples\android-19\connection\NetworkConnect\NetworkConnectSample\src\main\java.com\example\android\NetworkConnect\MainActivity.java中,该代码段根据Apache许可证2.0版授权,由Google编写。
/** Reads an InputStream and converts it to a String.
* @param stream InputStream containing HTML from targeted site.
* @param len Length of string that this method returns.
* @return String concatenated according to len parameter.
* @throws java.io.IOException
* @throws java.io.UnsupportedEncodingException
*/
private String readIt(InputStream stream, int len) throws IOException, UnsupportedEncodingException {
Reader reader = null;
reader = new InputStreamReader(stream, "UTF-8");
char[] buffer = new char[len];
reader.read(buffer);
return new String(buffer);
}
JDK 7/8应答,关闭流并仍然抛出IOException:
StringBuilder build = new StringBuilder();
byte[] buf = new byte[1024];
int length;
try (InputStream is = getInputStream()) {
while ((length = is.read(buf)) != -1) {
build.append(new String(buf, 0, length));
}
}
Raghu K Nair是唯一一个使用扫描仪的人。我使用的代码有点不同:
String convertToString(InputStream in){
Scanner scanner = new Scanner(in)
scanner.useDelimiter("\\A");
boolean hasInput = scanner.hasNext();
if (hasInput) {
return scanner.next();
} else {
return null;
}
}
关于分隔符:如何在Java Scanner中使用分隔符?
一个很好的方法是使用Apache Commons IOUItils将InputStream复制到StringWriter中。。。类似于
StringWriter writer = new StringWriter();
IOUtils.copy(inputStream, writer, encoding);
String theString = writer.toString();
甚至
// NB: does not close inputStream, you'll have to use try-with-resources for that
String theString = IOUtils.toString(inputStream, encoding);
或者,如果不想混合流和写入器,可以使用ByteArrayOutputStream。