BAEL-2015 Memory leaks in Java (#5295)

* BAEL-2015_Memory_leaks_in_Java * Ignored tests * Update NonStaticFieldsDemo.java * Corrected class name * converted tabspaces to whitespaces
2018-10-01 07:29:53 +05:30
parent b4aa279eaa
commit 317ed150a1
19 changed files with 410 additions and 0 deletions
@@ -0,0 +1,33 @@
+package com.baeldung.memoryleaks.equalshashcode;
+
+import static org.junit.Assert.assertTrue;
+
+import java.util.HashMap;
+import java.util.Map;
+
+import org.junit.Ignore;
+import org.junit.Test;
+
+public class PersonMemoryLeakUnitTest {
+    @Test
+    @Ignore // Test deliberately ignored as memory leak tests consume lots of resources
+    public void givenMap_whenEqualsAndHashCodeNotOverridden_thenMemoryLeak() {
+        Map<Person, Integer> map = new HashMap<Person, Integer>();
+        for(int i=0; i<10000000; i++) {
+            map.put(new Person("jon"), 1);
+        }
+        assertTrue(map.size() > 1);
+        System.out.print("Debug Point - VisuaLVM");
+    }
+    
+    @Test
+    @Ignore // Test deliberately ignored as memory leak tests consume lots of resources
+    public void givenMap_whenEqualsAndHashCodeOverridden_thenNoMemoryLeak() {
+        Map<PersonOptimized, Integer> map = new HashMap<PersonOptimized, Integer>();
+        for(int i=0; i<10000; i++) {
+            map.put(new PersonOptimized("jon"), 1);
+        }
+        assertTrue(map.size() == 1);
+        System.out.print("Debug Point - VisuaLVM");
+    }
+}
@@ -0,0 +1,28 @@
+package com.baeldung.memoryleaks.finalize;
+
+import org.junit.Ignore;
+import org.junit.Test;
+
+public class FinalizeMemoryLeakUnitTest {
+    @Test
+    @Ignore // Test deliberately ignored as memory leak tests consume lots of resources
+    public void givenObjectWithFinalizer_whenCreatingAndDestroyingThisObject_thenMemoryLeak() {
+        BulkyObject[] stock = new BulkyObject[100000];
+        
+        for(int i=0; i<100000; i++) {
+            stock[i] = new BulkyObject();
+        }
+        System.out.print("Debug Point - VisuaLVM");
+    }
+    
+    @Test
+    @Ignore // Test deliberately ignored as memory leak tests consume lots of resources
+    public void givenObjectWithoutFinalizer_whenCreatingAndDestroyingThisObject_thenNoMemoryLeak() {
+        BulkyObjectOptimized[] stock = new BulkyObjectOptimized[100000];
+        
+        for(int i=0; i<100000; i++) {
+            stock[i] = new BulkyObjectOptimized();
+        }
+        System.out.print("Debug Point - VisuaLVM");
+    }
+}
@@ -0,0 +1,20 @@
+package com.baeldung.memoryleaks.innerclass;
+
+import org.junit.Ignore;
+import org.junit.Test;
+
+public class StaticInnerClassMemoryLeakUnitTest {
+    @Test
+    @Ignore // Test deliberately ignored as memory leak tests consume lots of resources
+    public void givenUsingInnerClass_whenInitializingInnerClass_thenInnerClassHoldsReferenceOfOuterObject() {
+        InnerClassWrapper.SimpleInnerClass simpleInnerClassObj = new InnerClassWrapper().new SimpleInnerClass();
+        System.out.print("Debug Point - VisuaLVM");
+    }
+    
+    @Test
+    @Ignore // Test deliberately ignored as memory leak tests consume lots of resources
+    public void givenUsingStaticNestedClass_whenInitializingInnerClass_thenStaticNestedClassDoesntReferenceOuterObject() {
+        StaticNestedClassWrapper.StaticNestedClass staticNestedClassObj = new StaticNestedClassWrapper.StaticNestedClass();
+        System.out.print("Debug Point - VisuaLVM");
+    }
+}
@@ -0,0 +1,20 @@
+package com.baeldung.memoryleaks.internedstrings;
+
+import org.junit.Ignore;
+import org.junit.Test;
+
+public class StringInternMemoryLeakUnitTest {
+    @Test
+    @Ignore // Test deliberately ignored as memory leak tests consume lots of resources
+    public void givenJava6OrBelow_whenInterningLargeStrings_thenPermgenIncreases() {
+        new InternedString().readString();
+        System.out.print("Debug Point - VisuaLVM");
+    }
+    
+    @Test
+    @Ignore // Test deliberately ignored as memory leak tests consume lots of resources
+    public void givenJava6OrBelow_whenNotInterningLargeStrings_thenPermgenDoesntIncrease() {
+        new StringObject().readString();
+        System.out.print("Debug Point - VisuaLVM");
+    }
+}
@@ -0,0 +1,26 @@
+package com.baeldung.memoryleaks.staticfields;
+
+import java.util.ArrayList;
+import java.util.List;
+
+import org.junit.Ignore;
+import org.junit.Test;
+
+public class NonStaticFieldsMemoryLeakUnitTest {
+    public List<Double> list = new ArrayList<>();
+ 
+    public void populateList() {
+        for (int i = 0; i < 10000000; i++) {
+            list.add(Math.random());
+        }
+        System.out.println("Debug Point 2");
+    }
+ 
+    @Test
+    @Ignore // Test deliberately ignored as memory leak tests consume lots of resources
+    public void givenNonStaticLargeList_whenPopulatingList_thenListGarbageCollected() {
+        System.out.println("Debug Point 1");
+        new NonStaticFieldsMemoryLeakUnitTest().populateList();
+        System.out.println("Debug Point 3");
+    }
+}
@@ -0,0 +1,26 @@
+package com.baeldung.memoryleaks.staticfields;
+
+import java.util.ArrayList;
+import java.util.List;
+
+import org.junit.Ignore;
+import org.junit.Test;
+
+public class StaticFieldsMemoryLeakUnitTest {
+    public static List<Double> list = new ArrayList<>();
+ 
+    public void populateList() {
+        for (int i = 0; i < 10000000; i++) {
+            list.add(Math.random());
+        }
+        System.out.println("Debug Point 2");
+    }
+ 
+    @Test
+    @Ignore // Test deliberately ignored as memory leak tests consume lots of resources
+    public void givenStaticLargeList_whenPopulatingList_thenListIsNotGarbageCollected() {
+        System.out.println("Debug Point 1");
+        new StaticFieldsDemo().populateList();
+        System.out.println("Debug Point 3");
+    }
+}