defensive-coding-guide/modules/ROOT/examples/Java-Language-ReadArray.adoc
2022-01-13 20:42:40 +01:00

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static byte[] readBytes(InputStream in, int length) throws IOException {
final int startSize = 65536;
byte[] b = new byte[Math.min(length, startSize)];
int filled = 0;
while (true) {
int remaining = b.length - filled;
readFully(in, b, filled, remaining);
if (b.length == length) {
break;
}
filled = b.length;
if (length - b.length <= b.length) {
// Allocate final length. Condition avoids overflow.
b = Arrays.copyOf(b, length);
} else {
b = Arrays.copyOf(b, b.length * 2);
}
}
return b;
}
static void readFully(InputStream in,byte[] b, int off, int len)
throws IOException {
int startlen = len;
while (len > 0) {
int count = in.read(b, off, len);
if (count < 0) {
throw new EOFException();
}
off += count;
len -= count;
}
}