Since Java 9, the
readNBytes()
method can be added to the
InputStream
class. This method reads the requested number of bytes from an input stream into the given
byte array
. This method blocks until
len bytes
of input data have read, end of a stream is detected, or an exception is thrown. The
readNBytes()
method doesn't close an input stream. This method can be useful to avoid
memory
problems
with large files.
Syntax
在下面的示例中，我们在源文件夹中创建了一个名为“
Technology.txt
”的文件，其中包含简单的数据：
{ "JAVA", "PYTHON", "JAVASCRIPT", "SELENIUM", "SCALA"}。
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示例
输出
public int readNBytes(byte[] b, int off, int len) throws IOExceptionimport java.io.*;
import java.util.stream.*;
import java.nio.*;
import java.nio.file.*;
public class InputStreamReadNByteMethodTest {
InputStream inputStream = nputStreamReadNByteMethodTest.class.getResourceAsStream("Technology.txt");
public void testReadNBytes() throws Exception {
final byte[] data = new byte[10];
inputStream.readNBytes(data, 0, 7);
System.out.println(new String(data));
}
public static void main(String args[]) throws Exception {
InputStreamReadNByteMethodTest t = new InputStreamReadNByteMethodTest();
t.testReadNBytes();
}
}"JAVA",