improve logging and added precondition checks

scm-dao-xml/src/main/java/sonia/scm/store/FileBasedStore.java

@@ -109,6 +109,10 @@ public abstract class FileBasedStore<T> implements StoreBase<T>
   @Override
   public void remove(String id)
   {
+    Preconditions.checkArgument(!Strings.isNullOrEmpty(id),
+      "id argument is required");
+    logger.debug("try to delete store entry with id {}", id);
+
     File file = getFile(id);
 
     remove(file);
@@ -127,6 +131,8 @@ public abstract class FileBasedStore<T> implements StoreBase<T>
   @Override
   public T get(String id)
   {
+    Preconditions.checkArgument(!Strings.isNullOrEmpty(id),
+      "id argument is required");
     logger.trace("try to retrieve item with id {}", id);
 
     File file = getFile(id);
@@ -144,10 +150,10 @@ public abstract class FileBasedStore<T> implements StoreBase<T>
    */
   protected void remove(File file)
   {
+    logger.trace("delete store entry {}", file);
+
     if (file.exists() &&!file.delete())
     {
-      logger.debug("delete store entry {}", file);
-
       throw new StoreException(
         "could not delete store entry ".concat(file.getPath()));
     }

scm-dao-xml/src/main/java/sonia/scm/store/FileBlobStore.java

@@ -33,6 +33,8 @@ package sonia.scm.store;
 
 //~--- non-JDK imports --------------------------------------------------------
 
+import com.google.common.base.Preconditions;
+import com.google.common.base.Strings;
 import com.google.common.collect.ImmutableList;
 import com.google.common.collect.ImmutableList.Builder;
 
@@ -104,6 +106,10 @@ public class FileBlobStore extends FileBasedStore<Blob> implements BlobStore
   @Override
   public Blob create(String id)
   {
+    Preconditions.checkArgument(!Strings.isNullOrEmpty(id),
+      "id argument is required");
+    logger.debug("create new blob with id {}", id);
+
     File file = getFile(id);
 
     try
@@ -130,6 +136,7 @@ public class FileBlobStore extends FileBasedStore<Blob> implements BlobStore
   @Override
   public void remove(Blob blob)
   {
+    Preconditions.checkNotNull("blob argument is required");
     remove(blob.getId());
   }
 

scm-dao-xml/src/main/java/sonia/scm/store/JAXBDataStore.java

@@ -107,7 +107,7 @@ public class JAXBDataStore<T> extends FileBasedStore<T> implements DataStore<T>
   @Override
   public void put(String id, T item)
   {
-    logger.info("put item {} to store", id);
+    logger.debug("put item {} to store", id);
 
     File file = getFile(id);