### Eclipse Workspace Patch 1.0
#P apache-poi
Index: src/java/org/apache/poi/hssf/usermodel/HSSFWorkbook.java
===================================================================
--- src/java/org/apache/poi/hssf/usermodel/HSSFWorkbook.java	(revision 981695)
+++ src/java/org/apache/poi/hssf/usermodel/HSSFWorkbook.java	(working copy)
@@ -725,7 +725,8 @@
      *
      * @param sheetname the name for the new sheet. Note - certain length limits
      * apply. See {@link #setSheetName(int, String)}.
-     *
+     * @see {@link org.apache.poi.hssf.util.WorkbookUtil#createSafeSheetName(String nameProposal)}
+	 *      for a safe way to create valid names
      * @return HSSFSheet representing the new sheet.
      * @throws IllegalArgumentException
      *             if there is already a sheet present with a case-insensitive
Index: src/examples/src/org/apache/poi/hssf/usermodel/examples/NewSheet.java
===================================================================
--- src/examples/src/org/apache/poi/hssf/usermodel/examples/NewSheet.java	(revision 981695)
+++ src/examples/src/org/apache/poi/hssf/usermodel/examples/NewSheet.java	(working copy)
@@ -19,6 +19,7 @@
 
 import org.apache.poi.hssf.usermodel.HSSFWorkbook;
 import org.apache.poi.hssf.usermodel.HSSFSheet;
+import org.apache.poi.hssf.util.WorkbookUtil;
 
 import java.io.IOException;
 import java.io.FileOutputStream;
@@ -33,7 +34,8 @@
         HSSFWorkbook wb = new HSSFWorkbook();
         HSSFSheet sheet1 = wb.createSheet("new sheet");
         HSSFSheet sheet2 = wb.createSheet(); // create with default name
-        wb.setSheetName(1, "second sheet"); // setting sheet name later
+        final String name = "second sheet";
+		wb.setSheetName(1, WorkbookUtil.createSafeSheetName(name)); // setting sheet name later
         FileOutputStream fileOut = new FileOutputStream("workbook.xls");
         wb.write(fileOut);
         fileOut.close();
Index: src/java/org/apache/poi/hssf/util/WorkbookUtil.java
===================================================================
--- src/java/org/apache/poi/hssf/util/WorkbookUtil.java	(revision 0)
+++ src/java/org/apache/poi/hssf/util/WorkbookUtil.java	(revision 0)
@@ -0,0 +1,78 @@
+/* ====================================================================
+   Licensed to the Apache Software Foundation (ASF) under one or more
+   contributor license agreements.  See the NOTICE file distributed with
+   this work for additional information regarding copyright ownership.
+   The ASF 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.apache.poi.hssf.util;
+
+
+/**
+ * @author Martin W. Kirst (maki at bitkings de)
+ */
+public class WorkbookUtil {
+	
+	/**
+	 * Creates a valid sheet name, which is conform to the rules.
+	 * In any case, the result safely can be used for 
+	 * {@link org.apache.poi.hssf.usermodel.HSSFWorkbook#setSheetName(int, String)}.
+	 * <br>
+	 * Rules:
+	 * <ul>
+	 * <li>never null</li>
+	 * <li>minimum length is 1</li>
+	 * <li>maximum length is 31</li>
+	 * <li>doesn't contain special chars: / \ ? * ] [ </li>
+	 * <li>Sheet names must not begin or end with ' (apostrophe)</li>
+	 * </ul>
+	 * Invalid characters are replaced by one space character ' '.
+	 * 
+	 * @param nameProposal can be any string, will be truncated if necessary,
+	 *        allowed to be null
+	 * @return a valid string, "empty" if to short, "null" if null         
+	 */
+	public final static String createSafeSheetName(final String nameProposal) {
+		if (nameProposal == null) {
+			return "null";
+		}
+		if (nameProposal.length() < 1) {
+			return "empty";
+		}
+		final int length = Math.min(31, nameProposal.length());
+		final String shortenname = nameProposal.substring(0, length);
+		final StringBuilder result = new StringBuilder(shortenname);
+		for (int i=0; i<length; i++) {
+			char ch = result.charAt(i);
+			switch (ch) {
+				case '/':
+				case '\\':
+				case '?':
+				case '*':
+				case ']':
+				case '[':
+					result.setCharAt(i, ' ');
+					break;
+				case '\'':
+					if (i==0 || i==length-1) {
+						result.setCharAt(i, ' ');
+					}
+					break;
+				default:
+					// all other chars OK
+			}
+		}
+		return result.toString();
+	}
+
+}
Index: src/testcases/org/apache/poi/hssf/util/TestWorkbookUtil.java
===================================================================
--- src/testcases/org/apache/poi/hssf/util/TestWorkbookUtil.java	(revision 0)
+++ src/testcases/org/apache/poi/hssf/util/TestWorkbookUtil.java	(revision 0)
@@ -0,0 +1,88 @@
+/* ====================================================================
+   Licensed to the Apache Software Foundation (ASF) under one or more
+   contributor license agreements.  See the NOTICE file distributed with
+   this work for additional information regarding copyright ownership.
+   The ASF 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.apache.poi.hssf.util;
+
+import junit.framework.TestCase;
+
+/**
+ * Tests WorkbookUtil.
+ *
+ * @see org.apache.poi.hssf.util.WorkbookUtil
+ *
+ * @author Martin W. Kirst (maki at bitkings de)
+ */
+public final class TestWorkbookUtil extends TestCase {
+
+
+	/**
+	 * borrowed test cases from 
+	 * {@link org.apache.poi.hssf.record.TestBoundSheetRecord#testValidNames()}
+	 */
+	public void testCreateSafeNames() {
+		
+		String p = "Sheet1";
+		String actual = WorkbookUtil.createSafeSheetName(p);
+		assertEquals(p, actual);
+		
+		p = "O'Brien's sales";
+		actual = WorkbookUtil.createSafeSheetName(p);
+		assertEquals(p, actual);
+		
+		p = " data # ";
+		actual = WorkbookUtil.createSafeSheetName(p);
+		assertEquals(p, actual);
+		
+		p = "data $1.00";
+		actual = WorkbookUtil.createSafeSheetName(p);
+		assertEquals(p, actual);
+		
+		// now the replaced versions ...
+		actual = WorkbookUtil.createSafeSheetName("data?");
+		assertEquals("data ", actual);
+		
+		actual = WorkbookUtil.createSafeSheetName("abc/def");
+		assertEquals("abc def", actual);
+		
+		actual = WorkbookUtil.createSafeSheetName("data[0]");
+		assertEquals("data 0 ", actual);
+		
+		actual = WorkbookUtil.createSafeSheetName("data*");
+		assertEquals("data ", actual);
+		
+		actual = WorkbookUtil.createSafeSheetName("abc\\def");
+		assertEquals("abc def", actual);
+		
+		actual = WorkbookUtil.createSafeSheetName("'data");
+		assertEquals(" data", actual);
+		
+		actual = WorkbookUtil.createSafeSheetName("data'");
+		assertEquals("data ", actual);
+		
+		actual = WorkbookUtil.createSafeSheetName("d'at'a");
+		assertEquals("d'at'a", actual);
+		
+		actual = WorkbookUtil.createSafeSheetName(null);
+		assertEquals("null", actual);
+		
+		actual = WorkbookUtil.createSafeSheetName("");
+		assertEquals("empty", actual);
+		
+		actual = WorkbookUtil.createSafeSheetName("1234567890123456789012345678901TOOLONG");
+		assertEquals("1234567890123456789012345678901", actual);
+	}
+}
Index: src/java/org/apache/poi/hssf/record/BoundSheetRecord.java
===================================================================
--- src/java/org/apache/poi/hssf/record/BoundSheetRecord.java	(revision 981695)
+++ src/java/org/apache/poi/hssf/record/BoundSheetRecord.java	(working copy)
@@ -84,6 +84,8 @@
 	/**
 	 * Set the sheetname for this sheet.  (this appears in the tabs at the bottom)
 	 * @param sheetName the name of the sheet
+	 * @see {@link org.apache.poi.hssf.util.WorkbookUtil#createSafeSheetName(String nameProposal)}
+	 *      for a safe way to create valid names
 	 * @throws IllegalArgumentException if sheet name will cause excel to crash.
 	 */
 	public void setSheetname(String sheetName) {