update javadoc for cell/row copy

git-svn-id: https://svn.apache.org/repos/asf/poi/trunk@1893963 13f79535-47bb-0310-9956-ffa450edef68

poi-ooxml/src/main/java/org/apache/poi/xssf/usermodel/XSSFRow.java

@@ -638,11 +638,14 @@ public class XSSFRow implements Row, Comparable<XSSFRow> {
     }
 
     /**
-     * Copy the cells from srcRow to this row
+     * Copy the cells from srcRow to this row.
      * If this row is not a blank row, this will merge the two rows, overwriting
-     * the cells in this row with the cells in srcRow
-     * If srcRow is null, overwrite cells in destination row with blank values, styles, etc per cell copy policy
-     * srcRow may be from a different sheet in the same workbook
+     * the cells in this row with the cells in srcRow.
+     * If srcRow is null, overwrite cells in destination row with blank values, styles, etc per cell copy policy.
+     *
+     * Note that if you are copying from a non-XSSF row then you will need to disable style copying
+     * in the {@link CellCopyPolicy} (XSSF styles are not compatible with HSSF styles, for instance).
+     *
      * @param srcRow the rows to copy from
      * @param policy the policy to determine what gets copied
      */
@@ -657,6 +660,10 @@ public class XSSFRow implements Row, Comparable<XSSFRow> {
      * the cells in this row with the cells in srcRow
      * If srcRow is null, overwrite cells in destination row with blank values, styles, etc per cell copy policy
      * srcRow may be from a different sheet in the same workbook
+     *
+     * Note that if you are copying from a non-XSSF row then you will need to disable style copying
+     * in the {@link CellCopyPolicy} (XSSF styles are not compatible with HSSF styles, for instance).
+     *
      * @param srcRow the rows to copy from
      * @param policy the policy to determine what gets copied
      * @param context the context - see {@link CellCopyContext}

poi/src/main/java/org/apache/poi/hssf/usermodel/HSSFRow.java

@@ -801,11 +801,14 @@ public final class HSSFRow implements Row, Comparable<HSSFRow> {
     }
 
     /**
-     * Copy the cells from srcRow to this row
+     * Copy the cells from srcRow to this row.
      * If this row is not a blank row, this will merge the two rows, overwriting
-     * the cells in this row with the cells in srcRow
-     * If srcRow is null, overwrite cells in destination row with blank values, styles, etc per cell copy policy
-     * srcRow may be from a different sheet in the same workbook
+     * the cells in this row with the cells in srcRow.
+     * If srcRow is null, overwrite cells in destination row with blank values, styles, etc per cell copy policy.
+     *
+     * Note that if you are copying from a non-HSSF row then you will need to disable style copying
+     * in the {@link CellCopyPolicy} (HSSF styles are not compatible with XSSF styles, for instance).
+     *
      * @param srcRow the rows to copy from
      * @param policy the policy to determine what gets copied
      * @param context the context - see {@link CellCopyContext}

poi/src/main/java/org/apache/poi/ss/util/CellUtil.java

@@ -181,7 +181,10 @@ public final class CellUtil {
 
     /**
      * Copy cell value, formula and style, from srcCell per cell copy policy
-     * If srcCell is null, clears the cell value and cell style per cell copy policy
+     * If srcCell is null, clears the cell value and cell style per cell copy policy.
+     *
+     * Note that if you are copying from a source cell from a different type of then you may need to disable style copying
+     * in the {@link CellCopyPolicy} (HSSF styles are not compatible with XSSF styles, for instance).
      *
      * This does not shift references in formulas.
      *