001    /**
002     * ========================================
003     * JFreeReport : a free Java report library
004     * ========================================
005     *
006     * Project Info:  http://reporting.pentaho.org/
007     *
008     * (C) Copyright 2000-2007, by Object Refinery Limited, Pentaho Corporation and Contributors.
009     *
010     * This library is free software; you can redistribute it and/or modify it under the terms
011     * of the GNU Lesser General Public License as published by the Free Software Foundation;
012     * either version 2.1 of the License, or (at your option) any later version.
013     *
014     * This library is distributed in the hope that it will be useful, but WITHOUT ANY WARRANTY;
015     * without even the implied warranty of MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.
016     * See the GNU Lesser General Public License for more details.
017     *
018     * You should have received a copy of the GNU Lesser General Public License along with this
019     * library; if not, write to the Free Software Foundation, Inc., 59 Temple Place, Suite 330,
020     * Boston, MA 02111-1307, USA.
021     *
022     * [Java is a trademark or registered trademark of Sun Microsystems, Inc.
023     * in the United States and other countries.]
024     *
025     * ------------
026     * $Id: ExpressionDataRow.java 3525 2007-10-16 11:43:48Z tmorgner $
027     * ------------
028     * (C) Copyright 2000-2005, by Object Refinery Limited.
029     * (C) Copyright 2005-2007, by Pentaho Corporation.
030     */
031    package org.jfree.report.data;
032    
033    import java.util.HashMap;
034    
035    import org.jfree.report.DataFlags;
036    import org.jfree.report.DataRow;
037    import org.jfree.report.DataSourceException;
038    import org.jfree.report.flow.ReportContext;
039    import org.jfree.util.Log;
040    
041    /**
042     * A datarow for all expressions encountered in the report. This datarow is a
043     * stack-like structure, which allows easy adding and removing of expressions,
044     * even if these expressions have been cloned and or otherwisely modified.
045     *
046     * @author Thomas Morgner
047     */
048    public final class ExpressionDataRow implements DataRow
049    {
050      private ExpressionSlot[] expressions;
051      private int length;
052      private HashMap nameCache;
053      private GlobalMasterRow masterRow;
054      private ReportContext reportContext;
055    
056      public ExpressionDataRow(final GlobalMasterRow masterRow,
057                               final ReportContext reportContext,
058                               final int capacity)
059      {
060        this.masterRow = masterRow;
061        this.nameCache = new HashMap(capacity);
062        this.expressions = new ExpressionSlot[capacity];
063        this.reportContext = reportContext;
064      }
065    
066      private ExpressionDataRow(final GlobalMasterRow masterRow,
067                                final ExpressionDataRow previousRow)
068          throws CloneNotSupportedException
069      {
070        this.reportContext = previousRow.reportContext;
071        this.masterRow = masterRow;
072        this.nameCache = (HashMap) previousRow.nameCache.clone();
073        this.expressions = new ExpressionSlot[previousRow.expressions.length];
074        this.length = previousRow.length;
075        for (int i = 0; i < length; i++)
076        {
077          final ExpressionSlot expression = previousRow.expressions[i];
078          if (expression == null)
079          {
080            Log.debug("Error: Expression is null...");
081          }
082          else
083          {
084            expressions[i] = (ExpressionSlot) expression.clone();
085          }
086        }
087      }
088    
089      private void ensureCapacity(final int requestedSize)
090      {
091        final int capacity = this.expressions.length;
092        if (capacity > requestedSize)
093        {
094          return;
095        }
096        final int newSize = Math.max(capacity * 2, requestedSize + 10);
097    
098        final ExpressionSlot[] newExpressions = new ExpressionSlot[newSize];
099    
100        System.arraycopy(expressions, 0, newExpressions, 0, length);
101    
102        this.expressions = newExpressions;
103      }
104    
105      /**
106       * This adds the expression to the data-row and queries the expression for the
107       * first time.
108       *
109       * @param ex
110       * @param rd
111       * @throws DataSourceException
112       */
113      public synchronized void pushExpression(final ExpressionSlot expressionSlot)
114          throws DataSourceException
115      {
116        if (expressionSlot == null)
117        {
118          throw new NullPointerException();
119        }
120    
121        ensureCapacity(length + 1);
122    
123        this.expressions[length] = expressionSlot;
124        final String name = expressionSlot.getName();
125        if (name != null)
126        {
127          nameCache.put(name, expressionSlot);
128        }
129        length += 1;
130    
131        expressionSlot.updateDataRow(masterRow.getGlobalView());
132        // A manual advance to initialize the function.
133        expressionSlot.advance();
134        if (name != null)
135        {
136          final Object value = expressionSlot.getValue();
137          final MasterDataRowChangeEvent chEvent = new MasterDataRowChangeEvent
138              (MasterDataRowChangeEvent.COLUMN_ADDED, name, value);
139          masterRow.dataRowChanged(chEvent);
140        }
141      }
142    
143      public synchronized void pushExpressions(final ExpressionSlot[] expressionSlots)
144          throws DataSourceException
145      {
146        if (expressionSlots == null)
147        {
148          throw new NullPointerException();
149        }
150    
151        ensureCapacity(length + expressionSlots.length);
152        for (int i = 0; i < expressionSlots.length; i++)
153        {
154          final ExpressionSlot expression = expressionSlots[i];
155          if (expression == null)
156          {
157            continue;
158          }
159          pushExpression(expression);
160        }
161      }
162    
163      public synchronized void popExpressions(final int counter) throws
164          DataSourceException
165      {
166        for (int i = 0; i < counter; i++)
167        {
168          popExpression();
169        }
170      }
171    
172      public synchronized void popExpression() throws DataSourceException
173      {
174        if (length == 0)
175        {
176          return;
177        }
178        final String originalName = expressions[length - 1].getName();
179        final boolean preserve = expressions[length - 1].isPreserve();
180        this.expressions[length - 1] = null;
181        this.length -= 1;
182        if (originalName != null)
183        {
184          int otherIndex = -1;
185          for (int i = length - 1; i >= 0; i -= 1)
186          {
187            final ExpressionSlot expression = expressions[i];
188            if (originalName.equals(expression.getName()))
189            {
190              otherIndex = i;
191              break;
192            }
193          }
194          if (otherIndex == -1)
195          {
196            nameCache.remove(originalName);
197          }
198          else
199          {
200            nameCache.put(originalName, expressions[otherIndex]);
201          }
202    
203          if (preserve == false)
204          {
205            final MasterDataRowChangeEvent chEvent = new MasterDataRowChangeEvent
206                (MasterDataRowChangeEvent.COLUMN_REMOVED, originalName, null);
207            masterRow.dataRowChanged(chEvent);
208          }
209          // for preserved elements we do not send an remove-event.
210        }
211    
212      }
213    
214      /**
215       * Returns the value of the expressions or column in the tablemodel using the
216       * given column number as index. For functions and expressions, the
217       * <code>getValue()</code> method is called and for columns from the
218       * tablemodel the tablemodel method <code>getValueAt(row, column)</code> gets
219       * called.
220       *
221       * @param col the item index.
222       * @return the value.
223       * @throws IllegalStateException if the datarow detected a deadlock.
224       */
225      public Object get(final int col) throws DataSourceException
226      {
227        return expressions[col].getValue();
228      }
229    
230      /**
231       * Returns the value of the function, expressions or column using its specific
232       * name. The given name is translated into a valid column number and the the
233       * column is queried. For functions and expressions, the
234       * <code>getValue()</code> method is called and for columns from the
235       * tablemodel the tablemodel method <code>getValueAt(row, column)</code> gets
236       * called.
237       *
238       * @param col the item index.
239       * @return the value.
240       * @throws IllegalStateException if the datarow detected a deadlock.
241       */
242      public Object get(final String col) throws DataSourceException
243      {
244        final ExpressionSlot es = (ExpressionSlot) nameCache.get(col);
245        if (es == null)
246        {
247          return null;
248        }
249    
250        return es.getValue();
251      }
252    
253      /**
254       * Returns the name of the column, expressions or function. For columns from
255       * the tablemodel, the tablemodels <code>getColumnName</code> method is
256       * called. For functions, expressions and report properties the assigned name
257       * is returned.
258       *
259       * @param col the item index.
260       * @return the name.
261       */
262      public String getColumnName(final int col)
263      {
264        return expressions[col].getName();
265      }
266    
267      /**
268       * Returns the number of columns, expressions and functions and marked
269       * ReportProperties in the report.
270       *
271       * @return the item count.
272       */
273      public int getColumnCount()
274      {
275        return length;
276      }
277    
278      public DataFlags getFlags(final String col)
279      {
280        throw new UnsupportedOperationException();
281      }
282    
283      public DataFlags getFlags(final int col)
284      {
285        throw new UnsupportedOperationException();
286      }
287    
288      /**
289       * Advances to the next row and attaches the given master row to the objects
290       * contained in that client data row.
291       *
292       * @param master
293       * @param deepTraversing only advance expressions that have been marked as
294       *                       deeply traversing
295       * @return
296       */
297      public ExpressionDataRow advance(final GlobalMasterRow master,
298                                       final boolean deepTraversing)
299          throws DataSourceException
300      {
301        try
302        {
303          final ExpressionDataRow edr = new ExpressionDataRow(master, this);
304    
305          // It is defined, that new expressions get evaluated before any older
306          // expression.
307          for (int i = edr.length - 1; i >= 0; i--)
308          {
309            final ExpressionSlot expressionSlot = edr.expressions[i];
310            expressionSlot.updateDataRow(master.getGlobalView());
311            if (deepTraversing == false ||
312                (expressionSlot.isDeepTraversing()))
313            {
314              expressionSlot.advance();
315            }
316            // Query the value (once per advance) ..
317            final Object value = expressionSlot.getValue();
318            final String name = expressionSlot.getName();
319            if (name != null)
320            {
321              final MasterDataRowChangeEvent chEvent = new MasterDataRowChangeEvent
322                  (MasterDataRowChangeEvent.COLUMN_UPDATED, name, value);
323              master.dataRowChanged(chEvent);
324            }
325          }
326          return edr;
327        }
328        catch (CloneNotSupportedException e)
329        {
330          throw new DataSourceException("Cloning failed", e);
331        }
332      }
333    
334      public ExpressionDataRow derive(final GlobalMasterRow master)
335          throws DataSourceException
336      {
337        try
338        {
339          return new ExpressionDataRow(master, this);
340        }
341        catch (CloneNotSupportedException e)
342        {
343          throw new DataSourceException("Cloning failed", e);
344        }
345      }
346    
347      public ExpressionSlot[] getSlots()
348      {
349        // to be totally safe from any tampering, we would have to do some sort of
350        // deep-copy here.
351        final ExpressionSlot[] slots = new ExpressionSlot[length];
352        System.arraycopy(expressions, 0, slots, 0, length);
353        return slots;
354      }
355    }