Trigger deletion of objects of studies from storage system by exceed…

…ing of configured disk usage threshold fix #4584 Extend RESTful service to list configured Storage Systems to return configured Deleter Thresholds of Max Usable Space and current used disk space #4585
dcm4che · Oct 21, 2024 · 5b72b6d · 5b72b6d
1 parent 1a611d4
commit 5b72b6d
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diff --git a/dcm4chee-arc-assembly/src/main/resources/ldap/apacheds/dcm4chee-archive.ldif b/dcm4chee-arc-assembly/src/main/resources/ldap/apacheds/dcm4chee-archive.ldif
@@ -1,4 +1,4 @@
-# Generated by Apache Directory Studio on September 25, 2024, 6:44:48 PM
+# Generated by Apache Directory Studio on October 21, 2024, 5:22:28 PM
 
 # SCHEMA "DCM4CHEE-ARCHIVE"
 dn: cn=dcm4chee-archive, ou=schema
@@ -6457,6 +6457,35 @@ m-equality: booleanMatch
 m-syntax: 1.3.6.1.4.1.1466.115.121.1.7
 m-singleValue: TRUE
 
+dn: m-oid=1.2.40.0.13.1.15.110.3.484, ou=attributetypes, cn=dcm4chee-archive, ou
+ =schema
+objectclass: metaAttributeType
+objectclass: metaTop
+objectclass: top
+m-oid: 1.2.40.0.13.1.15.110.3.484
+m-name: dcmDeleterThresholdMaxUsableSpace
+m-description: Maximal Usable Space on Storage System to trigger deletion. If pr
+ esent, studies are deleted from the Storage System configured for cache (dcmSto
+ rageDuration=CACHE) or temporary (dcmStorageDuration=TEMPORARY) storage, if the
+  used disk space exceeds that value. Format [nn"[Used(s)"<schedule>"]"]nnn(MB|G
+ B|MiB|GiB). Only effective if dcmDeleterThresholdBlocksFilePath is also specifi
+ ed.
+m-equality: caseExactIA5Match
+m-syntax: 1.3.6.1.4.1.1466.115.121.1.26
+
+dn: m-oid=1.2.40.0.13.1.15.110.3.485, ou=attributetypes, cn=dcm4chee-archive, ou
+ =schema
+objectclass: metaAttributeType
+objectclass: metaTop
+objectclass: top
+m-oid: 1.2.40.0.13.1.15.110.3.485
+m-name: dcmDeleterThresholdBlocksFilePath
+m-description: Path of file containing the current used disk space in blocks (10
+ 24 bytes), periodically updated by an external application.
+m-equality: caseExactIA5Match
+m-syntax: 1.3.6.1.4.1.1466.115.121.1.26
+m-singleValue: TRUE
+
 dn: ou=comparators, cn=dcm4chee-archive, ou=schema
 objectclass: organizationalUnit
 objectclass: top
@@ -6587,6 +6616,8 @@ m-may: dcmStorageThreshold
 m-may: dcmStorageThresholdExceeded
 m-may: dcmStorageThresholdExceedsPermanently
 m-may: dcmDeleterThreshold
+m-may: dcmDeleterThresholdMaxUsableSpace
+m-may: dcmDeleterThresholdBlocksFilePath
 m-may: dcmDeleteStudiesOlderThan
 m-may: dcmDeleteStudiesReceivedBefore
 m-may: dcmDeleteStudiesNotUsedSince

diff --git a/dcm4chee-arc-assembly/src/main/resources/ldap/opendj/12-dcm4chee-archive.ldif b/dcm4chee-arc-assembly/src/main/resources/ldap/opendj/12-dcm4chee-archive.ldif
@@ -2357,6 +2357,15 @@ attributeTypes: ( 1.2.40.0.13.1.15.110.3.483 NAME 'dcmSingleExportStorageByStudy
   EQUALITY booleanMatch
   SYNTAX 1.3.6.1.4.1.1466.115.121.1.7
   SINGLE-VALUE )
+attributeTypes: ( 1.2.40.0.13.1.15.110.3.484 NAME 'dcmDeleterThresholdMaxUsableSpace'
+  DESC 'Maximal Usable Space on Storage System to trigger deletion. If present, studies are deleted from the Storage System configured for cache (dcmStorageDuration=CACHE) or temporary (dcmStorageDuration=TEMPORARY) storage, if the used disk space exceeds that value. Format [nn"[Used(s)"<schedule>"]"]nnn(MB|GB|MiB|GiB). Only effective if dcmDeleterThresholdBlocksFilePath is also specified.'
+  EQUALITY caseExactIA5Match
+  SYNTAX 1.3.6.1.4.1.1466.115.121.1.26 )
+attributeTypes: ( 1.2.40.0.13.1.15.110.3.485 NAME 'dcmDeleterThresholdBlocksFilePath'
+  DESC 'Path of file containing the current used disk space in blocks (1024 bytes), periodically updated by an external application.'
+  EQUALITY caseExactIA5Match
+  SYNTAX 1.3.6.1.4.1.1466.115.121.1.26
+  SINGLE-VALUE )
 objectClasses: ( 1.2.40.0.13.1.15.110.4.4 NAME 'dcmArchiveDevice'
   DESC 'DICOM Archive Device related information'
   SUP top AUXILIARY
@@ -2863,6 +2872,8 @@ objectClasses: ( 1.2.40.0.13.1.15.110.4.12 NAME 'dcmStorage'
     dcmStorageThresholdExceeded $
     dcmStorageThresholdExceedsPermanently $
     dcmDeleterThreshold $
+    dcmDeleterThresholdMaxUsableSpace $
+    dcmDeleterThresholdBlocksFilePath $
     dcmDeleteStudiesOlderThan $
     dcmDeleteStudiesReceivedBefore $
     dcmDeleteStudiesNotUsedSince $

diff --git a/dcm4chee-arc-assembly/src/main/resources/ldap/schema/dcm4chee-archive.schema b/dcm4chee-arc-assembly/src/main/resources/ldap/schema/dcm4chee-archive.schema
@@ -2830,6 +2830,17 @@ attributetype ( 1.2.40.0.13.1.15.110.3.483 NAME 'dcmSingleExportStorageByStudy'
   SYNTAX 1.3.6.1.4.1.1466.115.121.1.7
   SINGLE-VALUE )
 
+attributetype ( 1.2.40.0.13.1.15.110.3.484 NAME 'dcmDeleterThresholdMaxUsableSpace'
+  DESC 'Maximal Usable Space on Storage System to trigger deletion. If present, studies are deleted from the Storage System configured for cache (dcmStorageDuration=CACHE) or temporary (dcmStorageDuration=TEMPORARY) storage, if the used disk space exceeds that value. Format [nn"[Used(s)"<schedule>"]"]nnn(MB|GB|MiB|GiB). Only effective if dcmDeleterThresholdBlocksFilePath is also specified.'
+  EQUALITY caseExactIA5Match
+  SYNTAX 1.3.6.1.4.1.1466.115.121.1.26 )
+
+attributetype ( 1.2.40.0.13.1.15.110.3.485 NAME 'dcmDeleterThresholdBlocksFilePath'
+  DESC 'Path of file containing the current used disk space in blocks (1024 bytes), periodically updated by an external application.'
+  EQUALITY caseExactIA5Match
+  SYNTAX 1.3.6.1.4.1.1466.115.121.1.26
+  SINGLE-VALUE )
+
 objectclass ( 1.2.40.0.13.1.15.110.4.4 NAME 'dcmArchiveDevice'
   DESC 'DICOM Archive Device related information'
   SUP top AUXILIARY
@@ -3340,6 +3351,8 @@ objectclass ( 1.2.40.0.13.1.15.110.4.12 NAME 'dcmStorage'
     dcmStorageThresholdExceeded $
     dcmStorageThresholdExceedsPermanently $
     dcmDeleterThreshold $
+    dcmDeleterThresholdMaxUsableSpace $
+    dcmDeleterThresholdBlocksFilePath $
     dcmDeleteStudiesOlderThan $
     dcmDeleteStudiesReceivedBefore $
     dcmDeleteStudiesNotUsedSince $

diff --git a/dcm4chee-arc-assembly/src/main/resources/ldap/slapd/dcm4chee-archive-modify.ldif b/dcm4chee-arc-assembly/src/main/resources/ldap/slapd/dcm4chee-archive-modify.ldif
@@ -2357,6 +2357,15 @@ olcAttributeTypes: ( 1.2.40.0.13.1.15.110.3.483 NAME 'dcmSingleExportStorageBySt
   EQUALITY booleanMatch
   SYNTAX 1.3.6.1.4.1.1466.115.121.1.7
   SINGLE-VALUE )
+olcAttributeTypes: ( 1.2.40.0.13.1.15.110.3.484 NAME 'dcmDeleterThresholdMaxUsableSpace'
+  DESC 'Maximal Usable Space on Storage System to trigger deletion. If present, studies are deleted from the Storage System configured for cache (dcmStorageDuration=CACHE) or temporary (dcmStorageDuration=TEMPORARY) storage, if the used disk space exceeds that value. Format [nn"[Used(s)"<schedule>"]"]nnn(MB|GB|MiB|GiB). Only effective if dcmDeleterThresholdBlocksFilePath is also specified.'
+  EQUALITY caseExactIA5Match
+  SYNTAX 1.3.6.1.4.1.1466.115.121.1.26 )
+olcAttributeTypes: ( 1.2.40.0.13.1.15.110.3.485 NAME 'dcmDeleterThresholdBlocksFilePath'
+  DESC 'Path of file containing the current used disk space in blocks (1024 bytes), periodically updated by an external application.'
+  EQUALITY caseExactIA5Match
+  SYNTAX 1.3.6.1.4.1.1466.115.121.1.26
+  SINGLE-VALUE )
 -
 replace: olcObjectClasses
 olcObjectClasses: ( 1.2.40.0.13.1.15.110.4.4 NAME 'dcmArchiveDevice'
@@ -2865,6 +2874,8 @@ olcObjectClasses: ( 1.2.40.0.13.1.15.110.4.12 NAME 'dcmStorage'
     dcmStorageThresholdExceeded $
     dcmStorageThresholdExceedsPermanently $
     dcmDeleterThreshold $
+    dcmDeleterThresholdMaxUsableSpace $
+    dcmDeleterThresholdBlocksFilePath $
     dcmDeleteStudiesOlderThan $
     dcmDeleteStudiesReceivedBefore $
     dcmDeleteStudiesNotUsedSince $

diff --git a/dcm4chee-arc-assembly/src/main/resources/ldap/slapd/dcm4chee-archive.ldif b/dcm4chee-arc-assembly/src/main/resources/ldap/slapd/dcm4chee-archive.ldif
@@ -2356,6 +2356,15 @@ olcAttributeTypes: ( 1.2.40.0.13.1.15.110.3.483 NAME 'dcmSingleExportStorageBySt
   EQUALITY booleanMatch
   SYNTAX 1.3.6.1.4.1.1466.115.121.1.7
   SINGLE-VALUE )
+olcAttributeTypes: ( 1.2.40.0.13.1.15.110.3.484 NAME 'dcmDeleterThresholdMaxUsableSpace'
+  DESC 'Maximal Usable Space on Storage System to trigger deletion. If present, studies are deleted from the Storage System configured for cache (dcmStorageDuration=CACHE) or temporary (dcmStorageDuration=TEMPORARY) storage, if the used disk space exceeds that value. Format [nn"[Used(s)"<schedule>"]"]nnn(MB|GB|MiB|GiB). Only effective if dcmDeleterThresholdBlocksFilePath is also specified.'
+  EQUALITY caseExactIA5Match
+  SYNTAX 1.3.6.1.4.1.1466.115.121.1.26 )
+olcAttributeTypes: ( 1.2.40.0.13.1.15.110.3.485 NAME 'dcmDeleterThresholdBlocksFilePath'
+  DESC 'Path of file containing the current used disk space in blocks (1024 bytes), periodically updated by an external application.'
+  EQUALITY caseExactIA5Match
+  SYNTAX 1.3.6.1.4.1.1466.115.121.1.26
+  SINGLE-VALUE )
 olcObjectClasses: ( 1.2.40.0.13.1.15.110.4.4 NAME 'dcmArchiveDevice'
   DESC 'DICOM Archive Device related information'
   SUP top AUXILIARY
@@ -2862,6 +2871,8 @@ olcObjectClasses: ( 1.2.40.0.13.1.15.110.4.12 NAME 'dcmStorage'
     dcmStorageThresholdExceeded $
     dcmStorageThresholdExceedsPermanently $
     dcmDeleterThreshold $
+    dcmDeleterThresholdMaxUsableSpace $
+    dcmDeleterThresholdBlocksFilePath $
     dcmDeleteStudiesOlderThan $
     dcmDeleteStudiesReceivedBefore $
     dcmDeleteStudiesNotUsedSince $

diff --git a/...chee-arc-conf-json/src/main/java/org/dcm4chee/arc/conf/json/JsonArchiveConfiguration.java b/...chee-arc-conf-json/src/main/java/org/dcm4chee/arc/conf/json/JsonArchiveConfiguration.java
@@ -562,6 +562,7 @@ private void writeStorageDescriptor(JsonWriter writer, Collection<StorageDescrip
             writer.writeNotNullOrDef("dcmStorageClusterID", st.getStorageClusterID(), null);
             writer.writeNotNullOrDef("dcmStorageThreshold", st.getStorageThreshold(), null);
             writer.writeNotEmpty("dcmDeleterThreshold", st.getDeleterThresholdsAsStrings());
+            writer.writeNotEmpty("dcmDeleterThresholdMaxUsableSpace", st.getDeleterThresholdsMaxUsableSpaceAsStrings());
             writer.writeNotEmpty("dcmProperty", st.getProperties());
             writer.writeNotEmpty("dcmExternalRetrieveAET", st.getExternalRetrieveAETitles());
             writer.writeNotNullOrDef("dcmExternalRetrieveInstanceAvailability",
@@ -2444,6 +2445,9 @@ private void loadStorageDescriptorFrom(ArchiveDeviceExtension arcDev, JsonReader
                     case "dcmCheckMountFilePath":
                         st.setCheckMountFilePath(reader.stringValue());
                         break;
+                    case "dcmDeleterThresholdBlocksFilePath":
+                        st.setDeleterThresholdBlocksFilePath(reader.stringValue());
+                        break;
                     case "dcmFileOpenOption":
                         st.setFileOpenOptions(toOpenOptions(reader.stringArray()));
                         break;
@@ -2486,6 +2490,9 @@ private void loadStorageDescriptorFrom(ArchiveDeviceExtension arcDev, JsonReader
                     case "dcmDeleterThreshold":
                         st.setDeleterThresholdsFromStrings(reader.stringArray());
                         break;
+                    case "dcmDeleterThresholdMaxUseableSpace":
+                        st.setDeleterThresholdsMaxUseableSpaceFromStrings(reader.stringArray());
+                        break;
                     case "dcmProperty":
                         st.setProperties(reader.stringArray());
                         break;

diff --git a/...chee-arc-conf-ldap/src/main/java/org/dcm4chee/arc/conf/ldap/LdapArchiveConfiguration.java b/...chee-arc-conf-ldap/src/main/java/org/dcm4chee/arc/conf/ldap/LdapArchiveConfiguration.java
@@ -2816,6 +2816,8 @@ private Attributes storeTo(ConfigurationChanges.ModifiedObject ldapObj, StorageD
                 descriptor.isAltCreateDirectories(), false);
         LdapUtils.storeNotNullOrDef(ldapObj, attrs, "dcmCheckMountFilePath",
                 descriptor.getCheckMountFilePath(), null);
+        LdapUtils.storeNotNullOrDef(ldapObj, attrs, "dcmDeleterThresholdBlocksFilePath",
+                descriptor.getDeleterThresholdBlocksFilePath(), null);
         LdapUtils.storeNotEmpty(ldapObj, attrs, "dcmFileOpenOption",
                 descriptor.getFileOpenOptions(), StandardOpenOption.CREATE_NEW);
         LdapUtils.storeNotNullOrDef(ldapObj, attrs, "dcmLocationStatus",
@@ -2844,6 +2846,8 @@ private Attributes storeTo(ConfigurationChanges.ModifiedObject ldapObj, StorageD
                 descriptor.getStorageThreshold(), null);
         LdapUtils.storeNotEmpty(ldapObj, attrs, "dcmDeleterThreshold",
                 descriptor.getDeleterThresholdsAsStrings());
+        LdapUtils.storeNotEmpty(ldapObj, attrs, "dcmDeleterThresholdMaxUsableSpace",
+                descriptor.getDeleterThresholdsMaxUsableSpaceAsStrings());
         LdapUtils.storeNotEmpty(ldapObj, attrs, "dcmProperty",
                 descriptor.getProperties());
         LdapUtils.storeNotEmpty(ldapObj, attrs, "dcmExternalRetrieveAET",
@@ -2892,6 +2896,7 @@ private void loadStorageDescriptors(ArchiveDeviceExtension arcdev, String device
                 desc.setRetryCreateDirectories(LdapUtils.intValue(attrs.get("dcmRetryCreateDirectories"), 0));
                 desc.setAltCreateDirectories(LdapUtils.booleanValue(attrs.get("dcmAltCreateDirectories"), false));
                 desc.setCheckMountFilePath(LdapUtils.stringValue(attrs.get("dcmCheckMountFilePath"), null));
+                desc.setDeleterThresholdBlocksFilePath(LdapUtils.stringValue(attrs.get("dcmDeleterThresholdBlocksFilePath"), null));
                 desc.setFileOpenOptions(toOpenOptions(attrs.get("dcmFileOpenOption"), StandardOpenOption.CREATE_NEW));
                 desc.setLocationStatus(
                         LdapUtils.enumValue(LocationStatus.class, attrs.get("dcmLocationStatus"), LocationStatus.OK));
@@ -2912,6 +2917,8 @@ private void loadStorageDescriptors(ArchiveDeviceExtension arcdev, String device
                 desc.setStorageClusterID(LdapUtils.stringValue(attrs.get("dcmStorageClusterID"), null));
                 desc.setStorageThreshold(toStorageThreshold(attrs.get("dcmStorageThreshold")));
                 desc.setDeleterThresholdsFromStrings(LdapUtils.stringArray(attrs.get("dcmDeleterThreshold")));
+                desc.setDeleterThresholdsMaxUseableSpaceFromStrings(
+                        LdapUtils.stringArray(attrs.get("dcmDeleterThresholdMaxUsableSpace")));
                 desc.setProperties(LdapUtils.stringArray(attrs.get("dcmProperty")));
                 desc.setExternalRetrieveAETitles(LdapUtils.stringArray(attrs.get("dcmExternalRetrieveAET")));
                 desc.setExternalRetrieveInstanceAvailability(LdapUtils.enumValue(
@@ -3006,6 +3013,8 @@ private List<ModificationItem> storeDiffs(ConfigurationChanges.ModifiedObject ld
                 prev.isAltCreateDirectories(), desc.isAltCreateDirectories(), false);
         LdapUtils.storeDiffObject(ldapObj, mods, "dcmCheckMountFilePath",
                 prev.getCheckMountFilePath(), desc.getCheckMountFilePath(), null);
+        LdapUtils.storeDiffObject(ldapObj, mods, "dcmDeleterThresholdBlocksFilePath",
+                prev.getDeleterThresholdBlocksFilePath(), desc.getDeleterThresholdBlocksFilePath(), null);
         LdapUtils.storeDiff(ldapObj, mods, "dcmFileOpenOption",
                 prev.getFileOpenOptions(), desc.getFileOpenOptions(), StandardOpenOption.CREATE_NEW);
         LdapUtils.storeDiffObject(ldapObj, mods, "dcmLocationStatus",
@@ -3031,6 +3040,9 @@ private List<ModificationItem> storeDiffs(ConfigurationChanges.ModifiedObject ld
                 prev.getStorageThreshold(), desc.getStorageThreshold(), null);
         LdapUtils.storeDiff(ldapObj, mods, "dcmDeleterThreshold",
                 prev.getDeleterThresholdsAsStrings(), desc.getDeleterThresholdsAsStrings());
+        LdapUtils.storeDiff(ldapObj, mods, "dcmDeleterThresholdMaxUseableSpace",
+                prev.getDeleterThresholdsMaxUsableSpaceAsStrings(),
+                desc.getDeleterThresholdsMaxUsableSpaceAsStrings());
         LdapUtils.storeDiffProperties(ldapObj, mods, "dcmProperty", prev.getProperties(), desc.getProperties());
         LdapUtils.storeDiff(ldapObj, mods, "dcmExternalRetrieveAET",
                 prev.getExternalRetrieveAETitles(), desc.getExternalRetrieveAETitles());

diff --git a/dcm4chee-arc-conf/src/main/java/org/dcm4chee/arc/conf/StorageDescriptor.java b/dcm4chee-arc-conf/src/main/java/org/dcm4chee/arc/conf/StorageDescriptor.java
@@ -42,9 +42,10 @@
 import org.dcm4che3.util.AttributesFormat;
 import org.dcm4che3.util.StringUtils;
 
+import java.io.IOException;
+import java.io.InputStream;
 import java.net.URI;
-import java.nio.file.OpenOption;
-import java.nio.file.StandardOpenOption;
+import java.nio.file.*;
 import java.security.MessageDigest;
 import java.security.NoSuchAlgorithmException;
 import java.time.Period;
@@ -70,6 +71,7 @@ public enum OnStoragePathAlreadyExists {
     private AttributesFormat storagePathFormat = DEFAULT_ATTRIBUTES_FORMAT;
     private OnStoragePathAlreadyExists onStoragePathAlreadyExists = OnStoragePathAlreadyExists.RANDOM_PATH;
     private String checkMountFilePath;
+    private String deleterThresholdBlocksFilePath;
     private OpenOption[] fileOpenOptions = { StandardOpenOption.CREATE_NEW };
     private boolean altCreateDirectories;
     private int retryCreateDirectories;
@@ -97,6 +99,7 @@ public enum OnStoragePathAlreadyExists {
     private StorageDuration storageDuration = StorageDuration.PERMANENT;
     private StorageThreshold storageThreshold;
     private final ArrayList<DeleterThreshold> deleterThresholds = new ArrayList<>();
+    private final ArrayList<DeleterThreshold> deleterThresholdsMaxUseableSpace = new ArrayList<>();
     private final Map<String, String> properties = new HashMap<>();
     private final EnumMap<RetentionPeriod.DeleteStudies,List<RetentionPeriod>> retentionPeriods =
             new EnumMap(RetentionPeriod.DeleteStudies.class);
@@ -153,6 +156,36 @@ public void setCheckMountFilePath(String checkMountFilePath) {
         this.checkMountFilePath = checkMountFilePath;
     }
 
+    public String getDeleterThresholdBlocksFilePath() {
+        return deleterThresholdBlocksFilePath;
+    }
+
+    public void setDeleterThresholdBlocksFilePath(String deleterThresholdBlocksFilePath) {
+        this.deleterThresholdBlocksFilePath = deleterThresholdBlocksFilePath;
+    }
+
+    public long parseDeleterThresholdBlocksFile() throws IOException {
+        if (deleterThresholdBlocksFilePath == null)
+            return 0L;
+
+        Path path = Paths.get(deleterThresholdBlocksFilePath);
+        long l = Files.size(path);
+        if (l == 0 && l >= 16)
+            return 0L;
+
+        byte[] bytes = new byte[(int) l];
+        try (InputStream is = Files.newInputStream(path)) {
+            is.read(bytes);
+        }
+        long blocks = 0L;
+        for (byte b : bytes) {
+            int digit = (b & 0xFF) - '0';
+            if (digit < 0 || digit > 9) break;
+            blocks = blocks * 10 + digit;
+        }
+        return blocks;
+    }
+
     public OpenOption[] getFileOpenOptions() {
         return fileOpenOptions;
     }
@@ -377,29 +410,61 @@ public boolean hasDeleterThresholds() {
     }
 
     public String[] getDeleterThresholdsAsStrings() {
-        String[] ss = new String[deleterThresholds.size()];
-        for (int i = 0; i < ss.length; i++) {
-            ss[i] = deleterThresholds.get(i).toString();
-        }
-        return ss;
+        return getDeleterThresholdsAsStrings(deleterThresholds);
     }
 
     public List<DeleterThreshold> getDeleterThresholds() {
         return deleterThresholds;
     }
 
     public void setDeleterThresholdsFromStrings(String... ss) {
+        setDeleterThresholdsFromStrings(ss, deleterThresholds);
+    }
+
+    public long getDeleterThresholdMinUsableSpace(Calendar cal) {
+        return getDeleterThresholdDiskSpace(cal, this.deleterThresholds);
+    }
+
+    public boolean hasDeleterThresholdMaxUsableSpace() {
+        return !deleterThresholdsMaxUseableSpace.isEmpty();
+    }
+
+    public String[] getDeleterThresholdsMaxUsableSpaceAsStrings() {
+        return getDeleterThresholdsAsStrings(deleterThresholdsMaxUseableSpace);
+    }
+
+    public List<DeleterThreshold> getDeleterThresholdsMaxUseableSpace() {
+        return deleterThresholdsMaxUseableSpace;
+    }
+
+    public void setDeleterThresholdsMaxUseableSpaceFromStrings(String... ss) {
+        setDeleterThresholdsFromStrings(ss, deleterThresholdsMaxUseableSpace);
+    }
+
+    public long getDeleterThresholdMaxUsableSpace(Calendar cal) {
+        return getDeleterThresholdDiskSpace(cal, this.deleterThresholdsMaxUseableSpace);
+    }
+
+    private static String[] getDeleterThresholdsAsStrings(ArrayList<DeleterThreshold> deleterThresholds) {
+        String[] ss = new String[deleterThresholds.size()];
+        for (int i = 0; i < ss.length; i++) {
+            ss[i] = deleterThresholds.get(i).toString();
+        }
+        return ss;
+    }
+
+    private static void setDeleterThresholdsFromStrings(String[] ss, ArrayList<DeleterThreshold> deleterThresholds) {
         deleterThresholds.clear();
         for (String s : ss) {
             deleterThresholds.add(DeleterThreshold.valueOf(s));
         }
         Collections.sort(deleterThresholds);
     }
 
-    public long getDeleterThresholdMinUsableSpace(Calendar cal) {
+    private static long getDeleterThresholdDiskSpace(Calendar cal, ArrayList<DeleterThreshold> deleterThresholds) {
         for (DeleterThreshold deleterThreshold : deleterThresholds) {
             if (deleterThreshold.match(cal))
-                return deleterThreshold.getMinUsableDiskSpace();
+                return deleterThreshold.getDiskSpace();
         }
         return -1L;
     }