PropertyValueDAO and alf_prop_class implementation

- Contains patch that is incomplete i.e. future DAO unit tests won't work for incremental dev upgrades git-svn-id: https://svn.alfresco.com/repos/alfresco-enterprise/alfresco/HEAD/root@15405 c4b6b30b-aa2e-2d43-bbcb-ca4b014f7261
2025-08-07 17:49:17 +00:00 · 2009-07-25 03:23:04 +00:00
parent 7d43509474
commit 20b602324c
22 changed files with 1443 additions and 498 deletions
--- a/source/java/org/alfresco/repo/domain/CrcHelper.java
+++ b/source/java/org/alfresco/repo/domain/CrcHelper.java
@@ -0,0 +1,119 @@
+/*
+ * Copyright (C) 2005-2009 Alfresco Software Limited.
+ *
+ * This program is free software; you can redistribute it and/or
+ * modify it under the terms of the GNU General Public License
+ * as published by the Free Software Foundation; either version 2
+ * of the License, or (at your option) any later version.
+
+ * This program is distributed in the hope that it will be useful,
+ * but WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+ * GNU General Public License for more details.
+
+ * You should have received a copy of the GNU General Public License
+ * along with this program; if not, write to the Free Software
+ * Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301, USA.
+ * As a special exception to the terms and conditions of version 2.0 of
+ * the GPL, you may redistribute this Program in connection with Free/Libre
+ * and Open Source Software ("FLOSS") applications as described in Alfresco's
+ * FLOSS exception.  You should have recieved a copy of the text describing
+ * the FLOSS exception, and it is also available here:
+ * http://www.alfresco.com/legal/licensing" */
+
+package org.alfresco.repo.domain;
+
+import java.io.UnsupportedEncodingException;
+import java.util.zip.CRC32;
+
+import org.alfresco.util.Pair;
+
+/**
+ * Helper class to calculate CRC values for string persistence.
+ * 
+ * @author Derek Hulley
+ * @since 3.3
+ */
+public class CrcHelper
+{
+    public static final String EMPTY_STRING = ".empty";
+    
+    /**
+     * Calculate a persistable, unique pair of values that can be persisted in a database unique
+     * key and guarantee correct case-sensitivity.
+     * <p>
+     * While the short-string version of the value is always lowercase, the CRC is
+     * calculated from the virgin string if case-sensitivity is enforced; in the case-insensitive
+     * case, the CRC is calculated from a lowercase version of the string.
+     * <p>
+     * If the value is an empty string, then {@link #EMPTY_STRING} is used instead.  This ensures
+     * that persisted values don't fall foul of the Oracle empty string comparison "behaviour" i.e
+     * you should never persist an empty string in Oracle as it equates to a SQL <b>NULL</b>.
+     * 
+     * @param value             the raw value that will be persisted
+     * @param dataLength        the maximum number of characters that can be persisted
+     * @param useCharsFromStart <tt>true</tt> if the shortened string value must be made from
+     *                          the first characters of the string or <tt>false</tt> to use
+     *                          characters from the end of the string.
+     * @param caseSensitive     <tt>true</tt> if the resulting pair must be case-sensitive or
+     *                          <tt>false</tt> if the pair must be case-insensitive.
+     * @return                  Return the persistable pair.  The result will never be <tt>null</tt>,
+     *                          but the individual pair values will be <tt>null</tt> if the
+     *                          value given is <tt>null</tt>
+     */
+    public static Pair<String, Long> getStringCrcPair(
+            String value,
+            int dataLength,
+            boolean useCharsFromStart,
+            boolean caseSensitive)
+    {
+        String valueLowerCase;
+        if (value == null)
+        {
+            return new Pair<String, Long>(null, null);
+        }
+        else if (value.length() == 0)
+        {
+            value = CrcHelper.EMPTY_STRING;
+            valueLowerCase = value;
+        }
+        else
+        {
+            valueLowerCase = value.toLowerCase();
+        }
+        Long valueCrc;
+        try
+        {
+            CRC32 crc = new CRC32();
+            if (caseSensitive)
+            {
+                crc.update(value.getBytes("UTF-8"));
+            }
+            else
+            {
+                crc.update(valueLowerCase.getBytes("UTF-8"));
+            }
+            valueCrc = crc.getValue();
+        }
+        catch (UnsupportedEncodingException e)
+        {
+            throw new RuntimeException("UTF-8 encoding is not supported");
+        }
+        // Get the short value (case-sensitive or not)
+        String valueShort = null;
+        int valueLen = valueLowerCase.length();
+        if (valueLen < dataLength)
+        {
+            valueShort = value;
+        }
+        else if (useCharsFromStart)
+        {
+            valueShort = valueLowerCase.substring(0, dataLength - 1);
+        }
+        else
+        {
+            valueShort = valueLowerCase.substring(valueLen - dataLength);
+        }
+        return new Pair<String, Long>(valueShort, valueCrc);
+    }
+}