Java 8 InputStream to Byte Array | Generated by AI

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Good catch 👍 — in Java 8 InputStream.readAllBytes() does not exist (that was added in Java 9). You need to read the request body manually into a byte[].

Here are a few common ways:

1. Using ByteArrayOutputStream (most standard)

public static byte[] toByteArray(InputStream input) throws IOException {
    ByteArrayOutputStream buffer = new ByteArrayOutputStream();
    byte[] data = new byte[1024];
    int nRead;
    while ((nRead = input.read(data, 0, data.length)) != -1) {
        buffer.write(data, 0, nRead);
    }
    buffer.flush();
    return buffer.toByteArray();
}

In your wrapper constructor:

public CachedBodyHttpServletRequest(HttpServletRequest request) throws IOException {
    super(request);
    this.cachedBody = toByteArray(request.getInputStream());
}

2. Using Apache Commons IO (IOUtils)

If you already have Apache Commons IO on your classpath:

import org.apache.commons.io.IOUtils;

public CachedBodyHttpServletRequest(HttpServletRequest request) throws IOException {
    super(request);
    this.cachedBody = IOUtils.toByteArray(request.getInputStream());
}

3. Using Guava (ByteStreams)

If you have Guava:

import com.google.common.io.ByteStreams;

public CachedBodyHttpServletRequest(HttpServletRequest request) throws IOException {
    super(request);
    this.cachedBody = ByteStreams.toByteArray(request.getInputStream());
}

Final touch for logging

public String getBody() {
    return new String(this.cachedBody, StandardCharsets.UTF_8);
}

✅ So in Java 8, option #1 with ByteArrayOutputStream is the most portable. Option #2 or #3 is cleaner if you’re okay adding Commons IO or Guava.

Do you want me to refactor the full CachedBodyHttpServletRequest code into a Java 8–ready version (self-contained, no readAllBytes())?

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