[HER-1800] H3: Incomplete checkpoint listed in combo box

* Checkpoint.java
    remove previous attempt to use Lifecycle to catch error
* Checkpointable.java
    @Autowired(required=false) annotation for setRecoveryCheckpoint
* CheckpointService.java
    HasValidator implementation for post-build validity check; also check at launch (probably redundant)
* CheckpointValidator.java
    ensure validity stamp exists on any present Checkpoint

commons/src/main/java/org/archive/checkpointing/Checkpoint.java

@@ -31,14 +31,13 @@ import org.json.JSONException;
 import org.json.JSONObject;
 import org.springframework.beans.factory.InitializingBean;
 import org.springframework.beans.factory.annotation.Required;
-import org.springframework.context.Lifecycle;
 
 /**
  * Represents a single checkpoint, by its name and main store directory.
  * 
  * @contributor gojomo
  */
-public class Checkpoint implements InitializingBean, Lifecycle {
+public class Checkpoint implements InitializingBean {
     private final static Logger LOGGER =
         Logger.getLogger(Checkpoint.class.getName());
 
@@ -92,24 +91,6 @@ public class Checkpoint implements InitializingBean, Lifecycle {
         shortName = name.substring(0, name.indexOf("-"));
     }
     
-    boolean isRunning = false; 
-    public boolean isRunning() {
-        return isRunning;
-    }
-    public void start() {
-        if(isRunning) {
-            return; 
-        }
-        isRunning = true; 
-        if(!Checkpoint.hasValidStamp(checkpointDir.getFile())) {
-            throw new RuntimeException("checkpoint '"+checkpointDir.getFile().getAbsolutePath()+"' missing validity stamp file");
-        }
-    }
-    public void stop() {
-        isRunning = false; 
-    }
-    
-    
     public void setSuccess(boolean b) {
         success = b; 
     }

commons/src/main/java/org/archive/checkpointing/Checkpointable.java

@@ -21,6 +21,8 @@ package org.archive.checkpointing;
 
 import java.io.IOException;
 
+import org.springframework.beans.factory.annotation.Autowired;
+
 
 /**
  * Interface for objects that can checkpoint their state, possibly
@@ -72,5 +74,6 @@ public interface Checkpointable {
      * 
      * @param recoveryCheckpoint Checkpoint
      */
+    @Autowired(required=false)
     void setRecoveryCheckpoint(Checkpoint recoveryCheckpoint);
 }

engine/src/main/java/org/archive/crawler/framework/CheckpointService.java

@@ -37,12 +37,14 @@ import org.archive.checkpointing.Checkpoint;
 import org.archive.checkpointing.Checkpointable;
 import org.archive.crawler.reporting.CrawlStatSnapshot;
 import org.archive.spring.ConfigPath;
+import org.archive.spring.HasValidator;
 import org.springframework.beans.BeansException;
 import org.springframework.beans.factory.annotation.Autowired;
 import org.springframework.context.ApplicationContext;
 import org.springframework.context.ApplicationContextAware;
 import org.springframework.context.Lifecycle;
 import org.springframework.context.support.AbstractApplicationContext;
+import org.springframework.validation.Validator;
 
 /**
  * Executes checkpoints, and offers convenience methods for enumerating 
@@ -56,7 +58,7 @@ import org.springframework.context.support.AbstractApplicationContext;
  * @contributor gojomo
  * @contributor pjack
  */
-public class CheckpointService implements Lifecycle, ApplicationContextAware {
+public class CheckpointService implements Lifecycle, ApplicationContextAware, HasValidator {
     private final static Logger LOGGER =
         Logger.getLogger(CheckpointService.class.getName());
         
@@ -133,6 +135,16 @@ public class CheckpointService implements Lifecycle, ApplicationContextAware {
         if (isRunning) {
             return;
         }
+        // report if checkpoint incomplete/invalid
+        if(getRecoveryCheckpoint()!=null) {
+            File cpDir = getRecoveryCheckpoint().getCheckpointDir().getFile();
+            if(!Checkpoint.hasValidStamp(cpDir)) {
+                LOGGER.severe(
+                    "checkpoint '"+cpDir.getAbsolutePath()
+                    +"' missing validity stamp file; checkpoint data "
+                    +"may be missing or otherwise corrupt.");
+            }
+        }
         this.isRunning = true; 
         setupCheckpointTask();
     }
@@ -315,6 +327,9 @@ public class CheckpointService implements Lifecycle, ApplicationContextAware {
      */
     @SuppressWarnings("unchecked")
     public void setRecoveryCheckpointByName(String selectedCheckpoint) {
+        if(isRunning) {
+            throw new RuntimeException("may not set recovery Checkpoint after launch");
+        }
         Checkpoint recoveryCheckpoint = new Checkpoint();
         recoveryCheckpoint.getCheckpointDir().setBase(getCheckpointsDir());
         recoveryCheckpoint.getCheckpointDir().setPath(selectedCheckpoint);
@@ -326,4 +341,10 @@ public class CheckpointService implements Lifecycle, ApplicationContextAware {
             c.setRecoveryCheckpoint(recoveryCheckpoint);
         }
     }
+    
+    static Validator VALIDATOR = new CheckpointValidator();
+    @Override
+    public Validator getValidator() {
+        return VALIDATOR;
+    }
 } //EOC

engine/src/main/java/org/archive/crawler/framework/CheckpointValidator.java

@@ -0,0 +1,48 @@
+/*
+ *  This file is part of the Heritrix web crawler (crawler.archive.org).
+ *
+ *  Licensed to the Internet Archive (IA) by one or more individual 
+ *  contributors. 
+ *
+ *  The IA licenses this file to You under the Apache License, Version 2.0
+ *  (the "License"); you may not use this file except in compliance with
+ *  the License.  You may obtain a copy of the License at
+ *
+ *      http://www.apache.org/licenses/LICENSE-2.0
+ *
+ *  Unless required by applicable law or agreed to in writing, software
+ *  distributed under the License is distributed on an "AS IS" BASIS,
+ *  WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ *  See the License for the specific language governing permissions and
+ *  limitations under the License.
+ */
+package org.archive.crawler.framework;
+
+import org.archive.checkpointing.Checkpoint;
+import org.springframework.validation.Errors;
+import org.springframework.validation.Validator;
+
+public class CheckpointValidator implements Validator {
+
+    @Override
+    @SuppressWarnings("unchecked")
+    public boolean supports(Class cls) {
+        return Checkpoint.class.isAssignableFrom(cls);
+    }
+
+    @Override
+    public void validate(Object target, Errors errors) {
+        Checkpoint cp = ((CheckpointService)target).getRecoveryCheckpoint();
+        if(cp==null) {
+            return; 
+        }
+        if(!Checkpoint.hasValidStamp(cp.getCheckpointDir().getFile())) {
+            errors.rejectValue(
+                "recoveryCheckpoint.checkpointDir",
+                null,
+                "Configured recovery checkpoint "+cp.getName()
+                +" incomplete: lacks valid stamp file.");
+        }
+    }
+
+}