Preserve thread interrupt flag when wrapping InterruptedException

src/main/java/net/ladenthin/streambuffer/StreamBuffer.java

@@ -796,6 +796,7 @@ public int read() throws IOException {
                 }
             }
             catch (InterruptedException e) {
+                Thread.currentThread().interrupt();
                 throw new IOException(e);
             }
 
@@ -852,6 +853,7 @@ public int read(final byte b[], final int off, final int len) throws IOException
             try {
                 maximumAvailableBytes = tryWaitForEnoughBytes(missingBytes);
             } catch (InterruptedException e) {
+                Thread.currentThread().interrupt();
                 throw new IOException(e);
             }
 

src/test/java/net/ladenthin/streambuffer/StreamBufferTest.java

@@ -2409,13 +2409,15 @@ public void read_threadInterrupted_throwsIOException() throws Exception {
         final InputStream is = sb.getInputStream();
         final Semaphore started = new Semaphore(0);
         final Throwable[] caught = new Throwable[1];
+        final AtomicBoolean interruptFlagAfterCatch = new AtomicBoolean(false);
 
         Thread reader = new Thread(() -> {
             try {
                 started.release();
                 is.read(); // will block — no data, not closed
             } catch (IOException e) {
                 caught[0] = e;
+                interruptFlagAfterCatch.set(Thread.currentThread().isInterrupted());
             }
         });
 
@@ -2429,6 +2431,8 @@ public void read_threadInterrupted_throwsIOException() throws Exception {
         // assert
         assertThat("IOException should be thrown wrapping InterruptedException",
                 caught[0] instanceof IOException, is(true));
+        assertThat("Thread interrupt flag must be preserved after wrapping InterruptedException",
+                interruptFlagAfterCatch.get(), is(true));
     }
 
     @DisplayName("read(): array thread interrupted while waiting for second byte — throws io exception")
@@ -2440,6 +2444,7 @@ public void read_arrayThreadInterruptedWhileWaitingForSecondByte_throwsIOExcepti
         final OutputStream os = sb.getOutputStream();
         final Semaphore started = new Semaphore(0);
         final Throwable[] caught = new Throwable[1];
+        final AtomicBoolean interruptFlagAfterCatch = new AtomicBoolean(false);
 
         // write exactly 1 byte so the internal read() at the start of read(b,off,len)
         // succeeds immediately, then tryWaitForEnoughBytes blocks waiting for the second byte
@@ -2451,6 +2456,7 @@ public void read_arrayThreadInterruptedWhileWaitingForSecondByte_throwsIOExcepti
                 is.read(new byte[2], 0, 2);
             } catch (IOException e) {
                 caught[0] = e;
+                interruptFlagAfterCatch.set(Thread.currentThread().isInterrupted());
             }
         });
 
@@ -2464,6 +2470,8 @@ public void read_arrayThreadInterruptedWhileWaitingForSecondByte_throwsIOExcepti
         // assert
         assertThat("IOException should be thrown wrapping InterruptedException",
                 caught[0] instanceof IOException, is(true));
+        assertThat("Thread interrupt flag must be preserved after wrapping InterruptedException",
+                interruptFlagAfterCatch.get(), is(true));
     }
     }