Not able to disable output buffering of Java HTTP servlet

[Dexter via StackOverflow]

I have a project hosted on Google Apennine, standard runtime. I have defined a servlet which responds to a GET request with up-to 200kb data. Problem is that the servlet attempts to buffer a very large amount of the data before actually writing out.

I tried to put an upper limit on the buffering by doing,

resp.setBufferSize(1024);

But this makes no difference. An immediate log of the buffer size,

LOGGER.info("Using buffer of size " + resp.getBufferSize());

tells me that the buffer is of size 1024, but once the data is written, I again log the buffer size and it has grown to a very large amount depending upon the data written out.

Now, if I increase the output to sufficiently large amount I get an Exception, while writing out that data. The data itself is not stored anywhere, it is generated and written to the "ServletOutputStream" directly.

Error for /sizeTestServlet
java.lang.OutOfMemoryError: Java heap space
    at java.util.Arrays.copyOf(Arrays.java:2271)
    at java.io.ByteArrayOutputStream.grow(ByteArrayOutputStream.java:118)
    at java.io.ByteArrayOutputStream.ensureCapacity(ByteArrayOutputStream.java:93)
    at java.io.ByteArrayOutputStream.write(ByteArrayOutputStream.java:153)
    at java.io.OutputStream.write(OutputStream.java:75)
    at com.google.apphosting.runtime.jetty.RpcResponseGenerator.addContent(RpcResponseGenerator.java:65)
    at org.mortbay.jetty.AbstractGenerator$Output.write(AbstractGenerator.java:644)
    at org.mortbay.jetty.AbstractGenerator$Output.write(AbstractGenerator.java:589)

Is there some way to disable output buffering ?

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