Name: mlR10151 Date: 06/08/2001



The description of the MemoryCacheImageOutputStream.read(byte[] b, int off, int len)
says:

Reads up to len bytes from the stream, and stores them into b starting at index off. The number
of bytes read is returned. If no bytes can be read because the end of the stream has been
reached, -1 is returned.
...
Throws:
            IndexOutOfBoundsException - if off is negative, len is negative, or off + len is greater
            than b.length.

So, it must:
1. throw IOOBE if len < 0
2. return 0, if len == 0 and current position is not an EOF,

but it just returns -1 if len<=0.

To reproduce the bug run the following test on JDK-Merlin build b66:
===================== a.java =======================
import javax.imageio.stream.*;
import java.io.*;
public class a {
    public static void main(String[] args) throws Exception {
        ByteArrayOutputStream baos = new ByteArrayOutputStream();
        MemoryCacheImageOutputStream mcios = new MemoryCacheImageOutputStream(baos);

        byte[] ba = new byte[100];
        mcios.write(ba);
        mcios.seek(0);

        int result = mcios.read(ba, 0, 0);
        System.out.println((result == 0 ? "Passed" : "Failed") + " for len = 0");

        try {
            mcios.read(ba, 0, -1);
            System.out.println("Failed for len = -1");
        } catch (IndexOutOfBoundsException e) {
            System.out.println("Passed for len = -1");
        }
    }
}
===================== log =======================
% java -version
java version "1.4.0-beta_refresh"
Java(TM) 2 Runtime Environment, Standard Edition (build 1.4.0-beta_refresh-b66)
Java HotSpot(TM) Client VM (build 1.4.0-beta_refresh-b66, mixed mode)
% java a
Failed for len = 0
Failed for len = -1

The bug causes failure of the following test:
api/javax_imageio/stream/MemoryCacheImageOutputStream/index.html#read

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