Java Stream mit Puffer einlesen
Bin heute zufällig über folgende Methode gestolpert:
String readToString1(InputStream in) throws IOException
{
byte[]buf = new byte[256];
StringBuilder sb = new StringBuilder();
int n;
do {
n = in.read(buf, 0, 256);
if (n > 0) {
String s = new String(buf, 0, n, "UTF-8");
sb.append(s);
}
} while(n > 0);
return sb.toString();
}String readToString2(InputStream in) throws IOException
{
char[] buf = new char[128];
StringBuilder sb = new StringBuilder();
Reader r = new InputStreamReader(in, "UTF-8");
int n;
while((n = r.read(buf, 0, 128)) != -1)
{
sb.append(buf, 0, n);
}
return sb.toString();
}import static org.mockito.Mockito.*;
public static void main(String[] args) throws IOException
{
byte[] umlaut = "ö".getBytes("UTF-8");
byte[] inbuf = new byte[513];
inbuf[0] = 'X'; for(int i = 0;i<256;i++)
{inbuf[i*2+1] = umlaut[0]; inbuf[i*2+2] = umlaut[1]; }
InputStream in1 = spy(new ByteArrayInputStream(inbuf));
System.out.println(" readToString1()=" + readToString1(in1));
// make sure the inputstream was used with efficient block reads
verify(in1, times(4)).read(any(byte[].class), eq(0), eq(256));
verifyNoMoreInteractions(in1);
InputStream in2 = spy(new ByteArrayInputStream(inbuf));
System.out.println(" readToString2()=" + readToString2(in2));
// make sure the inputstream was used with efficient block reads
verify(in2, atMost(2)).read(any(byte[].class), eq(0), eq(8192));
verify(in2, atMost(1)).available();
verifyNoMoreInteractions(in2);
} readToString1()=Xööö...ööö??ööö...ööö??
readToString2()=Xööö...öööööööö...ööööö
