You are viewing a plain text version of this content. The canonical link for it is here.
Posted to issues@commons.apache.org by "Ken Weiner (JIRA)" <ji...@apache.org> on 2012/07/24 19:13:37 UTC

[jira] [Created] (IO-339) MaxBytesInputStream to limit size of bytes read

Ken Weiner created IO-339:
-----------------------------

             Summary: MaxBytesInputStream to limit size of bytes read
                 Key: IO-339
                 URL: https://issues.apache.org/jira/browse/IO-339
             Project: Commons IO
          Issue Type: Improvement
          Components: Streams/Writers
    Affects Versions: 2.4
            Reporter: Ken Weiner
            Priority: Minor


I wrote an input stream that stops when it reaches a configured size in bytes.  I found it useful for applications that download web pages and images, but want to enforce a max size to avoid memory problems for extremely large pages/images.

I was thinking that this class is generic and useful enough to include in the commons-io distribution.  Please consider it, and if it isn't appropriate for inclusion here, please recommend a better place to open source and share it.

{code}

package org.apache.commons.io.input;

import java.io.IOException;
import java.io.InputStream;

/**
 * An input stream that will end when the amount of bytes read reaches
 * the configured amount of maxBytes.
 * This is useful for preventing OutOfMemoryExceptions when downloading
 * very large files in cases where getting partial content is acceptable.
 * @author Ken Weiner
 */
public class MaxBytesInputStream extends CountingInputStream {
    private long maxBytes;

    public MaxBytesInputStream(InputStream is, long maxBytes) {
        super(is);
        this.maxBytes = maxBytes;
    }

    @Override
    protected void afterRead(int n) {
        super.afterRead((int) Math.min(n, this.maxBytes - getByteCount()));
    }

    @Override
    public int read() throws IOException {
        if (getByteCount() < this.maxBytes) {
            return super.read();
        }
        return -1;
    }

    @Override
    public int read(byte[] b) throws IOException {
        if (getByteCount() < this.maxBytes) {
            return super.read(b);
        }
        return -1;
    }

    @Override
    public int read(byte[] b, int off, int len) throws IOException {
        if (getByteCount() < this.maxBytes) {
            return super.read(b, off, len);
        }
        return -1;
    }
}
{code}

--
This message is automatically generated by JIRA.
If you think it was sent incorrectly, please contact your JIRA administrators: https://issues.apache.org/jira/secure/ContactAdministrators!default.jspa
For more information on JIRA, see: http://www.atlassian.com/software/jira

Re: [jira] [Created] (IO-339) MaxBytesInputStream to limit size of bytes read

Posted by Gary Gregory <GG...@rocketsoftware.com>.
Please create a JIRA and attach you code there. We cannot accept such code otherwise. 

Thank you!

Gary

On Jul 24, 2012, at 13:13, "Ken Weiner (JIRA)" <ji...@apache.org> wrote:

> Ken Weiner created IO-339:
> -----------------------------
> 
>             Summary: MaxBytesInputStream to limit size of bytes read
>                 Key: IO-339
>                 URL: https://issues.apache.org/jira/browse/IO-339
>             Project: Commons IO
>          Issue Type: Improvement
>          Components: Streams/Writers
>    Affects Versions: 2.4
>            Reporter: Ken Weiner
>            Priority: Minor
> 
> 
> I wrote an input stream that stops when it reaches a configured size in bytes.  I found it useful for applications that download web pages and images, but want to enforce a max size to avoid memory problems for extremely large pages/images.
> 
> I was thinking that this class is generic and useful enough to include in the commons-io distribution.  Please consider it, and if it isn't appropriate for inclusion here, please recommend a better place to open source and share it.
> 
> {code}
> 
> package org.apache.commons.io.input;
> 
> import java.io.IOException;
> import java.io.InputStream;
> 
> /**
> * An input stream that will end when the amount of bytes read reaches
> * the configured amount of maxBytes.
> * This is useful for preventing OutOfMemoryExceptions when downloading
> * very large files in cases where getting partial content is acceptable.
> * @author Ken Weiner
> */
> public class MaxBytesInputStream extends CountingInputStream {
>    private long maxBytes;
> 
>    public MaxBytesInputStream(InputStream is, long maxBytes) {
>        super(is);
>        this.maxBytes = maxBytes;
>    }
> 
>    @Override
>    protected void afterRead(int n) {
>        super.afterRead((int) Math.min(n, this.maxBytes - getByteCount()));
>    }
> 
>    @Override
>    public int read() throws IOException {
>        if (getByteCount() < this.maxBytes) {
>            return super.read();
>        }
>        return -1;
>    }
> 
>    @Override
>    public int read(byte[] b) throws IOException {
>        if (getByteCount() < this.maxBytes) {
>            return super.read(b);
>        }
>        return -1;
>    }
> 
>    @Override
>    public int read(byte[] b, int off, int len) throws IOException {
>        if (getByteCount() < this.maxBytes) {
>            return super.read(b, off, len);
>        }
>        return -1;
>    }
> }
> {code}
> 
> --
> This message is automatically generated by JIRA.
> If you think it was sent incorrectly, please contact your JIRA administrators: https://issues.apache.org/jira/secure/ContactAdministrators!default.jspa
> For more information on JIRA, see: http://www.atlassian.com/software/jira
> 
>