Author: ceki Date: Tue Oct 28 11:18:59 2008 New Revision: 1886 Modified: logback/trunk/logback-classic/src/main/java/org/slf4j/impl/CopyOnInheritThreadLocal.java logback/trunk/logback-classic/src/test/java/org/slf4j/impl/LogbackMDCAdapterTest.java Log: Fix LBCLASSIC-77 On application which do not put data in the MDC, the CopyOnInheriteThreadLocal would throw a NullPointerException. Modified: logback/trunk/logback-classic/src/main/java/org/slf4j/impl/CopyOnInheritThreadLocal.java ============================================================================== --- logback/trunk/logback-classic/src/main/java/org/slf4j/impl/CopyOnInheritThreadLocal.java (original) +++ logback/trunk/logback-classic/src/main/java/org/slf4j/impl/CopyOnInheritThreadLocal.java Tue Oct 28 11:18:59 2008 @@ -17,8 +17,12 @@ @Override protected HashMap<String, String> childValue( HashMap<String, String> parentValue) { - HashMap<String, String> hm = new HashMap<String, String>(parentValue); - return hm; + if (parentValue == null) { + return null; + } else { + HashMap<String, String> hm = new HashMap<String, String>(parentValue); + return hm; + } } } Modified: logback/trunk/logback-classic/src/test/java/org/slf4j/impl/LogbackMDCAdapterTest.java ============================================================================== --- logback/trunk/logback-classic/src/test/java/org/slf4j/impl/LogbackMDCAdapterTest.java (original) +++ logback/trunk/logback-classic/src/test/java/org/slf4j/impl/LogbackMDCAdapterTest.java Tue Oct 28 11:18:59 2008 @@ -27,6 +27,45 @@ int diff = new Random().nextInt(); /** + * Test that CopyOnInheritThreadLocal does not barf when the + * MDC hashmap is null + * + * @throws InterruptedException + */ + @Test + public void lbclassic77() throws InterruptedException { + LogbackMDCAdapter lma = new LogbackMDCAdapter(); + + HashMap<String, String> parentHM = getHashMapFromMDCAdapter(lma); + assertNull(parentHM); + + ChildThreadForMDCAdapter childThread = new ChildThreadForMDCAdapter(lma); + childThread.start(); + childThread.join(); + assertTrue(childThread.successul); + assertNull(childThread.childHM); + } + + class ChildThreadForMDCAdapter extends Thread { + + LogbackMDCAdapter logbackMDCAdapter; + boolean successul; + HashMap<String, String> childHM; + + ChildThreadForMDCAdapter(LogbackMDCAdapter logbackMDCAdapter) { + this.logbackMDCAdapter = logbackMDCAdapter; + } + + @Override + public void run() { + childHM = getHashMapFromMDCAdapter(logbackMDCAdapter); + logbackMDCAdapter.get(""); + successul = true; + } + } + + // ================================================= + /** * Test that LogbackMDCAdapter copies its hashmap when a child * thread inherits it. * @@ -38,32 +77,33 @@ String otherMDCKey = "o" + diff; MDC.put(mdcKey, mdcKey + A_SUFFIX); - HashMap<String, String> parentHM = getHM(); + HashMap<String, String> parentHM = getHashMapFromMDC(); - MyThread myThread = new MyThread(mdcKey, otherMDCKey); - myThread.start(); - myThread.join(); + ChildThreadForMDC childThread = new ChildThreadForMDC(mdcKey, otherMDCKey); + childThread.start(); + childThread.join(); assertNull(MDC.get(otherMDCKey)); - assertTrue(myThread.successul); - assertTrue(parentHM != myThread.childHM); + assertTrue(childThread.successul); + assertTrue(parentHM != childThread.childHM); } - class MyThread extends Thread { + + class ChildThreadForMDC extends Thread { String mdcKey; String otherMDCKey; boolean successul; HashMap<String, String> childHM; - MyThread(String mdcKey, String otherMDCKey) { + ChildThreadForMDC(String mdcKey, String otherMDCKey) { this.mdcKey = mdcKey; this.otherMDCKey = otherMDCKey; } @Override public void run() { - childHM = getHM(); + childHM = getHashMapFromMDC(); MDC.put(otherMDCKey, otherMDCKey + A_SUFFIX); assertNotNull(MDC.get(mdcKey)); @@ -73,10 +113,14 @@ } } - HashMap<String, String> getHM() { - LogbackMDCAdapter lma = (LogbackMDCAdapter) MDC.getMDCAdapter(); + HashMap<String, String> getHashMapFromMDCAdapter(LogbackMDCAdapter lma) { CopyOnInheritThreadLocal copyOnInheritThreadLocal = lma.copyOnInheritThreadLocal; return copyOnInheritThreadLocal.get(); + } + HashMap<String, String> getHashMapFromMDC() { + LogbackMDCAdapter lma = (LogbackMDCAdapter) MDC.getMDCAdapter(); + CopyOnInheritThreadLocal copyOnInheritThreadLocal = lma.copyOnInheritThreadLocal; + return copyOnInheritThreadLocal.get(); } }