org.jfree.report.function: public class: TotalGroupSumFunction

org.jfree.report.function
public class: TotalGroupSumFunction [javadoc | source]

java.lang.Object
   org.jfree.report.function.AbstractExpression
      org.jfree.report.function.AbstractFunction
         org.jfree.report.function.TotalGroupSumFunction

All Implemented Interfaces:
Function, Expression, Serializable

A report function that calculates the sum of one field (column) from the Data-Row. This function produces a global total. The total sum of the group is known when the group processing starts and the report is not performing a prepare-run. The sum is calculated in the prepare run and recalled in the printing run.

The function can be used in two ways:

to calculate a sum for the entire report;
to calculate a sum within a particular group;

This function expects its input values to be either java.lang.Number instances or Strings that can be parsed to java.lang.Number instances using a java.text.DecimalFormat.

The function undestands two parameters, the field parameter is required and denotes the name of an ItemBand-field which gets summed up.

The parameter group denotes the name of a group. When this group is started, the counter gets reseted to null. This parameter is optional.

author: Thomas - Morgner

Constructor:
public TotalGroupSumFunction() { results = new HashMap(); } Constructs a new function. Initially the function has no name...be sure to assign one before using the function.

Constructor:

 public TotalGroupSumFunction() {
                        
    results = new HashMap();
}

Constructs a new function.

Initially the function has no name...be sure to assign one before using the function.

Method from org.jfree.report.function.TotalGroupSumFunction Summary:
getField, getGroup, getInstance, getValue, groupStarted, itemsAdvanced, reportInitialized, setField, setGroup

Methods from org.jfree.report.function.AbstractFunction:
groupFinished, groupStarted, itemsAdvanced, itemsFinished, itemsStarted, reportDone, reportFinished, reportInitialized, reportStarted

Methods from org.jfree.report.function.AbstractExpression:
clone, getDataRow, getDependencyLevel, getInstance, getName, getReportConfiguration, getResourceBundleFactory, getRuntime, isActive, isDeepTraversing, isPreserve, setActive, setDependencyLevel, setName, setPreserve, setRuntime

Methods from java.lang.Object:
equals, getClass, hashCode, notify, notifyAll, toString, wait, wait, wait

Method from org.jfree.report.function.TotalGroupSumFunction Detail:
public String getField() { return field; } Returns the field used by the function. The field name corresponds to a column name in the report's data-row.
public String getGroup() { return group; } Returns the name of the group to be totalled.
public Expression getInstance() { final TotalGroupSumFunction function = (TotalGroupSumFunction) super.getInstance(); function.result = null; function.results = new HashMap(); return function; } Return a completly separated copy of this function. The copy does no longer share any changeable objects with the original function.
public Object getValue() { return result; } Return the current function value. The value depends (obviously) on the function implementation. For example, a page counting function will return the current page number.
public void groupStarted(ReportEvent event) { if (FunctionUtilities.isDefinedGroup(getGroup(), event) == false) { // wrong group ... return; } groupStateKey = event.getState().getProcessKey(); if (FunctionUtilities.isDefinedPrepareRunLevel(this, event)) { result = new BigDecimal(0); results.put(globalStateKey, result); results.put(groupStateKey, result); } else { // Activate the current group, which was filled in the prepare run. result = (BigDecimal) results.get(groupStateKey); } } Receives notification that a group has started.
public void itemsAdvanced(ReportEvent event) { if (field == null) { return; } if (FunctionUtilities.isDefinedPrepareRunLevel(this, event) == false) { return; } final Object fieldValue = event.getDataRow().get(getField()); try { final Number n = (Number) fieldValue; if (n instanceof BigDecimal) { final BigDecimal bd = (BigDecimal) n; result = result.add(bd); results.put(globalStateKey, result); if (groupStateKey != null) { results.put(groupStateKey, result); } } else if (n instanceof Number) { result = result.add(new BigDecimal(String.valueOf(n))); results.put(globalStateKey, result); if (groupStateKey != null) { results.put(groupStateKey, result); } } } catch (Exception e) { TotalGroupSumFunction.logger.error("TotalGroupSumFunction.itemsAdvanced(): problem adding number." + fieldValue, e); } } Receives notification that a row of data is being processed.
public void reportInitialized(ReportEvent event) { globalStateKey = event.getState().getProcessKey(); if (FunctionUtilities.isDefinedPrepareRunLevel(this, event)) { results.clear(); result = new BigDecimal(0); results.put(globalStateKey, result); } else { result = (BigDecimal) results.get(globalStateKey); } } Receives notification that the report has started.
public void setField(String field) { this.field = field; } Sets the field name for the function. The field name corresponds to a column name in the report's data-row.
public void setGroup(String group) { this.group = group; } Defines the name of the group to be totalled. If the name is null, all groups are totalled.

Method from org.jfree.report.function.TotalGroupSumFunction Detail:

 public String getField() {
    return field;
}

Returns the field used by the function. The field name corresponds to a column name in the report's data-row.

 public String getGroup() {
    return group;
}

Returns the name of the group to be totalled.

 public Expression getInstance() {
    final TotalGroupSumFunction function = (TotalGroupSumFunction) super.getInstance();
    function.result = null;
    function.results = new HashMap();
    return function;
}

Return a completly separated copy of this function. The copy does no longer share any changeable objects with the original function.

 public Object getValue() {
    return result;
}

The value depends (obviously) on the function implementation. For example, a page counting function will return the current page number.

 public  void groupStarted(ReportEvent event) {
    if (FunctionUtilities.isDefinedGroup(getGroup(), event) == false)
    {
      // wrong group ...
      return;
    }
    groupStateKey = event.getState().getProcessKey();
    if (FunctionUtilities.isDefinedPrepareRunLevel(this, event))
    {
      result = new BigDecimal(0);
      results.put(globalStateKey, result);
      results.put(groupStateKey, result);
    }
    else
    {
      // Activate the current group, which was filled in the prepare run.
      result = (BigDecimal) results.get(groupStateKey);
    }
}

Receives notification that a group has started.

 public  void itemsAdvanced(ReportEvent event) {
    if (field == null)
    {
      return;
    }
    if (FunctionUtilities.isDefinedPrepareRunLevel(this, event) == false)
    {
      return;
    }
    final Object fieldValue = event.getDataRow().get(getField());
    try
    {
      final Number n = (Number) fieldValue;
      if (n instanceof BigDecimal)
      {
        final BigDecimal bd = (BigDecimal) n;
        result = result.add(bd);
        results.put(globalStateKey, result);
        if (groupStateKey != null)
        {
          results.put(groupStateKey, result);
        }
      }
      else if (n instanceof Number)
      {
        result = result.add(new BigDecimal(String.valueOf(n)));
        results.put(globalStateKey, result);
        if (groupStateKey != null)
        {
          results.put(groupStateKey, result);
        }
      }
    }
    catch (Exception e)
    {
      TotalGroupSumFunction.logger.error("TotalGroupSumFunction.itemsAdvanced(): problem adding number." + fieldValue, e);
    }
}

Receives notification that a row of data is being processed.

 public  void reportInitialized(ReportEvent event) {
    globalStateKey = event.getState().getProcessKey();
    if (FunctionUtilities.isDefinedPrepareRunLevel(this, event))
    {
      results.clear();
      result = new BigDecimal(0);
      results.put(globalStateKey, result);
    }
    else
    {
      result = (BigDecimal) results.get(globalStateKey);
    }
}

Receives notification that the report has started.

 public  void setField(String field) {
    this.field = field;
}

Sets the field name for the function. The field name corresponds to a column name in the report's data-row.

 public  void setGroup(String group) {
    this.group = group;
}

Defines the name of the group to be totalled. If the name is null, all groups are totalled.