fix: correct usage of cleaner api

Author: Sam Shpuntoff

src/main/java/com/mapzen/jpostal/AddressExpander.java

@@ -5,7 +5,6 @@
 import java.util.concurrent.atomic.AtomicBoolean;
 
 public class AddressExpander {
-    private static final Cleaner cleaner = Cleaner.create();
     private static final AtomicBoolean isShutdown = new AtomicBoolean(false);
 
     private volatile static AddressExpander instance = null;
@@ -79,8 +78,20 @@ public String[] expandAddressWithOptions(String address, ExpanderOptions options
             }
         }
 
-        // Register cleanup
-        this.cleanable = cleaner.register(this, () -> {
+        this.cleanable = Utils.registerForCleanup(this, new CleanupAction(isShutdown));
+    }
+    
+    private static class CleanupAction implements Runnable {
+        private final AtomicBoolean isShutdown;
+        private final LibPostal libPostal;
+        
+        CleanupAction(AtomicBoolean isShutdown, LibPostal libPostal) {
+            this.isShutdown = isShutdown;
+            this.libPostal = libPostal;
+        }
+        
+        @Override
+        public void run() {
             if (isShutdown.compareAndSet(false, true)) {
                 try {
                     synchronized (libPostal) {
@@ -90,6 +101,6 @@ public String[] expandAddressWithOptions(String address, ExpanderOptions options
                     System.err.println("AddressExpander cleaner error: " + e.getMessage());
                 }
             }
-        });
+        }
     }
-}
+}

src/main/java/com/mapzen/jpostal/AddressParser.java

@@ -6,7 +6,6 @@
 import java.util.concurrent.atomic.AtomicBoolean;
 
 public class AddressParser {
-    private static final Cleaner cleaner = Cleaner.create();
     private static final AtomicBoolean isShutdown = new AtomicBoolean(false);
 
     private volatile static AddressParser instance = null;
@@ -80,8 +79,20 @@ public ParsedComponent[] parseAddressWithOptions(String address, ParserOptions o
             }
         }
 
-        // Register cleanup
-        this.cleanable = cleaner.register(this, () -> {
+        this.cleanable = Utils.registerForCleanup(this, new CleanupAction(isShutdown));
+    }
+    
+    private static class CleanupAction implements Runnable {
+        private final AtomicBoolean isShutdown;
+        private final LibPostal libPostal;
+        
+        CleanupAction(AtomicBoolean isShutdown, LibPostal libPostal) {
+            this.isShutdown = isShutdown;
+            this.libPostal = libPostal;
+        }
+        
+        @Override
+        public void run() {
             if (isShutdown.compareAndSet(false, true)) {
                 try {
                     synchronized (libPostal) {
@@ -91,6 +102,6 @@ public ParsedComponent[] parseAddressWithOptions(String address, ParserOptions o
                     System.err.println("AddressParser cleaner error: " + e.getMessage());
                 }
             }
-        });
+        }
     }
 }

src/main/java/com/mapzen/jpostal/LibPostal.java

@@ -4,7 +4,6 @@
 import java.util.concurrent.atomic.AtomicBoolean;
 
 final class LibPostal {
-    private static final Cleaner cleaner = Cleaner.create();
     private static final AtomicBoolean isShutdown = new AtomicBoolean(false);
 
     private final Config config;
@@ -25,17 +24,7 @@ private LibPostal(final Config config) {
         }
 
         this.config = config;
-        
-        // Register cleanup
-        this.cleanable = cleaner.register(this, () -> {
-            if (isShutdown.compareAndSet(false, true)) {
-                try {
-                    teardown();
-                } catch (Exception e) {
-                    System.err.println("LibPostal teardown error: " + e.getMessage());
-                }
-            }
-        });
+        this.cleanable = Utils.registerForCleanup(this, new CleanupAction(isShutdown));
     }
 
     Config getConfig() {
@@ -60,4 +49,23 @@ static LibPostal getInstance(final Config config) {
        }
        return instance;
     }
-}
+    
+    private static class CleanupAction implements Runnable {
+        private final AtomicBoolean isShutdown;
+        
+        CleanupAction(AtomicBoolean isShutdown) {
+            this.isShutdown = isShutdown;
+        }
+        
+        @Override
+        public void run() {
+            if (isShutdown.compareAndSet(false, true)) {
+                try {
+                    teardown();
+                } catch (Exception e) {
+                    System.err.println("LibPostal teardown error: " + e.getMessage());
+                }
+            }
+        }
+    }
+}

src/main/java/com/mapzen/jpostal/Utils.java

@@ -0,0 +1,16 @@
+package com.mapzen.jpostal;
+
+import java.lang.ref.Cleaner;
+
+final class Utils {
+    
+    private static final Cleaner CLEANER = Cleaner.create();
+    
+    private Utils() {
+        throw new UnsupportedOperationException("Utility class");
+    }
+    
+    static Cleaner.Cleanable registerForCleanup(Object obj, Runnable cleanupAction) {
+        return CLEANER.register(obj, cleanupAction);
+    }
+}