Merge pull request #8125 from eugenp/revert-8119-BAEL-3275-2

Revert "BAEL-3275: Using blocking queue for pub-sub"

patterns/design-patterns-structural/src/test/java/com/baeldung/proxy/ProxyPatternIntegrationTest.java

@@ -0,0 +1,41 @@
+package com.baeldung.proxy;
+
+import static com.baeldung.util.LoggerUtil.LOG;
+import static org.hamcrest.CoreMatchers.is;
+import static org.junit.Assert.assertThat;
+
+import java.util.List;
+
+import org.apache.log4j.spi.LoggingEvent;
+import org.junit.After;
+import org.junit.Before;
+import org.junit.Test;
+
+public class ProxyPatternIntegrationTest {
+    public static TestAppenderDP appender;
+    
+    @Before
+    public void setUp() {
+        appender = new TestAppenderDP();
+        LOG.addAppender(appender);
+    }
+    
+    @Test
+    public void givenExpensiveObjectProxy_WhenObjectInitialized_thenInitializedOnlyOnce() {
+        ExpensiveObject object = new ExpensiveObjectProxy();
+        object.process();
+        object.process();
+
+        final List<LoggingEvent> log = appender.getLog();
+        
+        assertThat((String) log.get(0).getMessage(), is("Loading initial configuration.."));
+        assertThat((String) log.get(1).getMessage(), is("processing complete."));
+        assertThat((String) log.get(2).getMessage(), is("processing complete."));
+    }
+    
+    @After
+    public void tearDown() {
+        LOG.removeAppender(appender);
+    }
+}
+

patterns/design-patterns-structural/src/test/java/com/baeldung/proxy/TestAppenderDP.java

@@ -0,0 +1,29 @@
+package com.baeldung.proxy;
+
+import java.util.ArrayList;
+import java.util.List;
+
+import org.apache.log4j.AppenderSkeleton;
+import org.apache.log4j.spi.LoggingEvent;
+
+public class TestAppenderDP extends AppenderSkeleton {
+    private final List<LoggingEvent> log = new ArrayList<LoggingEvent>();
+
+    @Override
+    public boolean requiresLayout() {
+        return false;
+    }
+
+    @Override
+    protected void append(final LoggingEvent loggingEvent) {
+        log.add(loggingEvent);
+    }
+
+    @Override
+    public void close() {
+    }
+
+    public List<LoggingEvent> getLog() {
+        return new ArrayList<LoggingEvent>(log);
+    }
+}