flowable/flowable-engine · error · FlowableException

Could not read from inputstream

Error message

Could not read from inputstream

What it means

Thrown by InputStreamSource.getInputStream() when reading the wrapped InputStream into a byte array fails with an IOException. The source caches bytes lazily, so this occurs on the first getInputStream() call. The original IOException is the cause.

Solutions

1. Inspect the cause IOException for the underlying read failure
2. Ensure the InputStream is fresh/unconsumed when constructing InputStreamSource
3. Check the underlying resource (file/URL/network) is available and readable
4. Retry the deployment with a newly opened stream

Example fix

// before
InputStreamSource src = new InputStreamSource(sharedStream); // stream already consumed upstream
// after
InputStreamSource src = new InputStreamSource(new FileInputStream("process.bpmn20.xml"));

if (inputStream == null) throw new IllegalArgumentException("stream must not be null");
if (inputStream.available() <= 0 && expectsData) logger.warn("stream may be empty/already consumed");

try {
    InputStream is = source.getInputStream();
} catch (FlowableException e) {
    logger.error("Reading deployment resource failed", e.getCause());
    throw new IOException("retry with a fresh stream", e);
}

When it happens

Trigger: getBytesFromInputStream throws IOException while draining the wrapped stream — e.g. the stream was already consumed and closed, or the underlying resource became unreadable mid-read.

Common situations: Deploying a process definition where the resource stream was already read elsewhere; network-backed streams (URLs, remote repos) dropping mid-read; file removed between open and read.

Understand the failure class

Background: "failed to read file", EACCES, ENOENT and "could not read <path>" errors: when a program can't read a file from disk — this error's family across 49 libraries.

Related errors

• byte array for resource
• byte array for resource
• Could not completely read inputstream
• could not get byte array from resource
• could not get byte array from resource

AI-assisted analysis of flowable/flowable-engine@d6d39ce1c6 (2026-09-11). Data as JSON: /api/errors/71aa08522739cbcd. Report an issue: GitHub.

Appendix: source

Thrown at modules/flowable-engine-common/src/main/java/org/flowable/common/engine/impl/util/io/InputStreamSource.java:47

    // The bpmn parsers needs to go over the stream at least twice:
    // Once for the schema validation and once for the parsing itself.
    // So we keep the content of the inputstream in memory so we can
    // re-read it.

    protected BufferedInputStream inputStream;
    protected byte[] bytes;

    public InputStreamSource(InputStream inputStream) {
        this.inputStream = new BufferedInputStream(inputStream);
    }

    @Override
    public InputStream getInputStream() {
        if (bytes == null) {
            try {
                bytes = getBytesFromInputStream(inputStream);
            } catch (IOException e) {
                throw new FlowableException("Could not read from inputstream", e);
            }
        }
        return new BufferedInputStream(new ByteArrayInputStream(bytes));
    }

    @Override
    public String toString() {
        return "InputStream";
    }

    public byte[] getBytesFromInputStream(InputStream inStream) throws IOException {
        long length = inStream.available();
        byte[] bytes = new byte[(int) length];

        int offset = 0;
        int numRead = 0;
        while (offset < bytes.length && (numRead = inStream.read(bytes, offset, bytes.length - offset)) >= 0) {
            offset += numRead;

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