public CategoryToPieDataset(CategoryDataset source,
    TableOrder extract,
    int index) 
{
                                                                                         
        if (extract == null) {
            throw new IllegalArgumentException("Null 'extract' argument.");
        }
        this.source = source;
        if (this.source != null) {
            this.source.addChangeListener(this);
        }
        this.extract = extract;
        this.index = index;
}

An adaptor class that converts any CategoryDataset into a PieDataset , by taking the values from a single row or column.

If source is null, the created dataset will be empty.

Parameters:

source - the source dataset (null permitted).

extract - extract data from rows or columns? (null not permitted).

index - the row or column index.

 public  void datasetChanged(DatasetChangeEvent event) 
{
        fireDatasetChanged();
}

Sends a DatasetChangeEvent to all registered listeners, with this (not the underlying) dataset as the source.

 public boolean equals(Object obj) 
{
        if (obj == this) {
            return true;
        }
        if (!(obj instanceof PieDataset)) {
            return false;
        }
        PieDataset that = (PieDataset) obj;
        int count = getItemCount();
        if (that.getItemCount() != count) {
            return false;
        }
        for (int i = 0; i <  count; i++) {
            Comparable k1 = getKey(i);
            Comparable k2 = that.getKey(i);
            if (!k1.equals(k2)) {
                return false;
            }
            Number v1 = getValue(i);
            Number v2 = that.getValue(i);
            if (v1 == null) {
                if (v2 != null) {
                    return false;
                }
            }
            else {
                if (!v1.equals(v2)) {
                    return false;
                }
            }
        }
        return true;
}

Tests this dataset for equality with an arbitrary object, returning true if obj is a dataset containing the same keys and values in the same order as this dataset.

 public int getExtractIndex() 
{
        return this.index;
}

Returns the index of the row or column from which to extract the data.

 public TableOrder getExtractType() 
{
        return this.extract;
}

Returns the extract type, which determines whether data is read from one row or one column of the underlying dataset.

 public int getIndex(Comparable key) 
{
        int result = -1;
        if (this.source != null) {
            if (this.extract == TableOrder.BY_ROW) {
                result = this.source.getColumnIndex(key);
            }
            else if (this.extract == TableOrder.BY_COLUMN) {
                result = this.source.getRowIndex(key);
            }
        }
        return result;
}

Returns the index for a given key, or -1 if there is no such key.

 public int getItemCount() 
{
        int result = 0;
        if (this.source != null) {
            if (this.extract == TableOrder.BY_ROW) {
                result = this.source.getColumnCount();
            }
            else if (this.extract == TableOrder.BY_COLUMN) {
                result = this.source.getRowCount();
            }
        }
        return result;
}

Returns the number of items (values) in the collection. If the underlying dataset is null, this method returns zero.

 public Comparable getKey(int index) 
{
        Comparable result = null;
        if (index <  0 || index  >= getItemCount()) {
            // this includes the case where the underlying dataset is null
            throw new IndexOutOfBoundsException("Invalid 'index': " + index);
        }
        if (this.extract == TableOrder.BY_ROW) {
            result = this.source.getColumnKey(index);
        }
        else if (this.extract == TableOrder.BY_COLUMN) {
            result = this.source.getRowKey(index);
        }
        return result;
}

Returns the key at the specified index.

 public List getKeys() 
{
        List result = Collections.EMPTY_LIST;
        if (this.source != null) {
            if (this.extract == TableOrder.BY_ROW) {
                result = this.source.getColumnKeys();
            }
            else if (this.extract == TableOrder.BY_COLUMN) {
                result = this.source.getRowKeys();
            }
        }
        return result;
}

Returns the keys for the dataset.

If the underlying dataset is null, this method returns an empty list.

 public CategoryDataset getUnderlyingDataset() 
{
        return this.source;
}

Returns the underlying dataset.

 public Number getValue(int item) 
{
        Number result = null;
        if (item <  0 || item  >= getItemCount()) {
            // this will include the case where the underlying dataset is null
            throw new IndexOutOfBoundsException(
                    "The 'item' index is out of bounds.");
        }
        if (this.extract == TableOrder.BY_ROW) {
            result = this.source.getValue(this.index, item);
        }
        else if (this.extract == TableOrder.BY_COLUMN) {
            result = this.source.getValue(item, this.index);
        }
        return result;
}

Returns a value from the dataset.

 public Number getValue(Comparable key) 
{
        Number result = null;
        int keyIndex = getIndex(key);
        if (keyIndex != -1) {
            if (this.extract == TableOrder.BY_ROW) {
                result = this.source.getValue(this.index, keyIndex);
            }
            else if (this.extract == TableOrder.BY_COLUMN) {
                result = this.source.getValue(keyIndex, this.index);
            }
        }
        return result;
}

Returns the value for a given key. If the key is not recognised, the method should return null (but note that null can be associated with a valid key also).