四种JVM内存溢出演示

qui910 · qui910 · commit fe3fd09081ff · 2020-07-15T23:50:37.000+08:00
diff --git a/src/main/java/com/prd/jvm/HelloConstantOutOfMemory.java b/src/main/java/com/prd/jvm/HelloConstantOutOfMemory.java
@@ -0,0 +1,20 @@
+package com.prd.jvm;
+
+import java.util.ArrayList;
+import java.util.List;
+
+/**
+ * 演示常量池溢出问题
+ * -verbose:gc -Xms10M -Xmx10M -Xss128k -XX:+PrintGCDetails
+ */
+public class HelloConstantOutOfMemory {
+
+    public static void main(String[] args) {
+
+        List<String> stringList = new ArrayList<>();
+        int item = 0;
+        while (true) {
+            stringList.add(String.valueOf(item++).intern());
+        }
+    }
+}
diff --git a/src/main/java/com/prd/jvm/HelloDirectMemoryOutOfMemory.java b/src/main/java/com/prd/jvm/HelloDirectMemoryOutOfMemory.java
@@ -0,0 +1,20 @@
+package com.prd.jvm;
+
+import java.nio.ByteBuffer;
+
+/**
+ * 通过NIO测试直接内存溢出
+ * -verbose:gc -Xms10M -Xmx10M -XX:MaxDirectMemorySize=10M -Xss128k -XX:+PrintGCDetails
+ */
+public class HelloDirectMemoryOutOfMemory {
+    private  static final int ONE_MB=1024*1024*1024;
+
+    private static int count=1;
+
+    public static void main(String[] args) {
+        while(true) {
+            ByteBuffer buffer = ByteBuffer.allocateDirect(ONE_MB);
+            count++;
+        }
+    }
+}
diff --git a/src/main/java/com/prd/jvm/HelloHeapOutOfMemory.java b/src/main/java/com/prd/jvm/HelloHeapOutOfMemory.java
@@ -0,0 +1,24 @@
+package com.prd.jvm;
+
+import java.util.ArrayList;
+import java.util.List;
+
+/**
+ * 堆内存溢出样式
+ * -verbose:gc -Xms10M -Xmx10M -XX:MaxDirectMemortSize=5M
+ * -Xss128k -XX:+PrintGCDetails -XX:+HeapDumpOnOutOfMemoryError -XX:HeapDumpPath=./heapdump.hprof
+ */
+public class HelloHeapOutOfMemory {
+
+    private static class Person{}
+
+    public static void main(String[] args) {
+        System.out.println("HelloHeapOutOfMemory");
+        List<Person> personList = new ArrayList();
+        int nums = 0;
+        while(true) {
+            personList.add(new Person());
+            System.out.println("构造第"+(++nums)+"个实例");
+        }
+    }
+}
diff --git a/src/main/java/com/prd/jvm/HelloStackOverFlow.java b/src/main/java/com/prd/jvm/HelloStackOverFlow.java
@@ -0,0 +1,21 @@
+package com.prd.jvm;
+
+/**
+ * 演示栈空间溢出
+ * -verbose:gc -Xms10M -Xmx10M -Xss128k -XX:+PrintGCDetails
+ * Stack栈，是线程私有的
+ */
+public class HelloStackOverFlow {
+    private int nums;
+
+    public void count() {
+        nums++;
+        count();
+    }
+
+    public static void main(String[] args) {
+        System.out.println("HelloStackOverFlow");
+        HelloStackOverFlow flow = new HelloStackOverFlow();
+        flow.count();
+    }
+}
