QPID-3592: ensure that the 'used credit' values are decremented when message transfer commands 'completed' following a message.stop command attempt to restore their credit (to no effect due to the 0 credit limit) when using 0-10 Window credit mode. Add unit test, and break CreditManager dependency on ServerMessages by passing the required size value rather than the message itself.

git-svn-id: https://svn.apache.org/repos/asf/qpid/trunk/qpid@1200801 13f79535-47bb-0310-9956-ffa450edef68

1 files changed, 63 insertions, 0 deletions

diff --git a/java/broker/src/test/java/org/apache/qpid/server/flow/WindowCreditManagerTest.java b/java/broker/src/test/java/org/apache/qpid/server/flow/WindowCreditManagerTest.java
new file mode 100644
index 0000000000..61a9e0b446
--- /dev/null
+++ b/java/broker/src/test/java/org/apache/qpid/server/flow/WindowCreditManagerTest.java
@@ -0,0 +1,63 @@
+package org.apache.qpid.server.flow;
+
+import org.apache.qpid.test.utils.QpidTestCase;
+
+public class WindowCreditManagerTest extends QpidTestCase
+{
+    WindowCreditManager _creditManager;
+
+    protected void setUp() throws Exception
+    {
+        super.setUp();
+        _creditManager = new WindowCreditManager();
+    }
+
+    /**
+     * Tests that after the credit limit is cleared (e.g. from a message.stop command), credit is
+     * restored (e.g. from completed MessageTransfer) without increasing the available credit, and
+     * more credit is added, that the 'used' count is correct and the proper values for bytes
+     * and message credit are returned along with appropriate 'hasCredit' results (QPID-3592).
+     */
+    public void testRestoreCreditDecrementsUsedCountAfterCreditClear()
+    {
+        assertEquals("unexpected credit value", 0, _creditManager.getMessageCredit());
+        assertEquals("unexpected credit value", 0, _creditManager.getBytesCredit());
+
+        //give some message credit
+        _creditManager.addCredit(1, 0);
+        assertFalse("Manager should not 'haveCredit' due to having 0 bytes credit", _creditManager.hasCredit());
+        assertEquals("unexpected credit value", 1, _creditManager.getMessageCredit());
+        assertEquals("unexpected credit value", 0, _creditManager.getBytesCredit());
+
+        //give some bytes credit
+        _creditManager.addCredit(0, 1);
+        assertTrue("Manager should 'haveCredit'", _creditManager.hasCredit());
+        assertEquals("unexpected credit value", 1, _creditManager.getMessageCredit());
+        assertEquals("unexpected credit value", 1, _creditManager.getBytesCredit());
+
+        //use all the credit
+        _creditManager.useCreditForMessage(1);
+        assertEquals("unexpected credit value", 0, _creditManager.getBytesCredit());
+        assertEquals("unexpected credit value", 0, _creditManager.getMessageCredit());
+        assertFalse("Manager should not 'haveCredit'", _creditManager.hasCredit());
+
+        //clear credit out (eg from a message.stop command)
+        _creditManager.clearCredit();
+        assertEquals("unexpected credit value", 0, _creditManager.getBytesCredit());
+        assertEquals("unexpected credit value", 0, _creditManager.getMessageCredit());
+        assertFalse("Manager should not 'haveCredit'", _creditManager.hasCredit());
+
+        //restore credit (e.g the original message transfer command got completed)
+        //this should not increase credit, because it is now limited to 0
+        _creditManager.restoreCredit(1, 1);
+        assertEquals("unexpected credit value", 0, _creditManager.getBytesCredit());
+        assertEquals("unexpected credit value", 0, _creditManager.getMessageCredit());
+        assertFalse("Manager should not 'haveCredit'", _creditManager.hasCredit());
+
+        //give more credit to open the window again
+        _creditManager.addCredit(1, 1);
+        assertEquals("unexpected credit value", 1, _creditManager.getBytesCredit());
+        assertEquals("unexpected credit value", 1, _creditManager.getMessageCredit());
+        assertTrue("Manager should 'haveCredit'", _creditManager.hasCredit());
+    }
+}