*
*
* all
* first-last
* 1,2,3,4
*
* or combinations thereof. The range is internally converted from
* 1-based to 0-based (so methods that set or get numbers not in string
* format should use 0-based numbers).
*
* @author Len Trigg (trigg@cs.waikato.ac.nz)
* @version $Revision: 1.10 $
*/
public class Range implements Serializable {
/** Record the string representations of the columns to delete */
Vector m_RangeStrings = new Vector();
/** Whether matching should be inverted */
boolean m_Invert;
/** The array of flags for whether an column is selected */
boolean [] m_SelectFlags;
/** Store the maximum value permitted in the range. -1 indicates that
no upper value has been set */
int m_Upper = -1;
/** Default constructor. */
public Range() {
}
/**
* Constructor to set initial range.
*
* @param rangeList the initial range
* @exception IllegalArgumentException if the range list is invalid
*/
public Range(String rangeList) {
setRanges(rangeList);
}
/**
* Sets the value of "last".
*
* @param newUpper the value of "last"
*/
public void setUpper(int newUpper) {
if (newUpper >= 0) {
m_Upper = newUpper;
setFlags();
}
}
/**
* Gets whether the range sense is inverted, i.e. all except
* the values included by the range string are selected.
*
* @return whether the matching sense is inverted
*/
public boolean getInvert() {
return m_Invert;
}
/**
* Sets whether the range sense is inverted, i.e. all except
* the values included by the range string are selected.
*
* @param newSetting true if the matching sense is inverted
*/
public void setInvert(boolean newSetting) {
m_Invert = newSetting;
}
/**
* Gets the string representing the selected range of values
*
* @return the range selection string
*/
public String getRanges() {
String result = null;
Enumeration enum = m_RangeStrings.elements();
while (enum.hasMoreElements()) {
if (result == null) {
result = (String)enum.nextElement();
} else {
result += ',' + (String)enum.nextElement();
}
}
return (result == null) ? "" : result;
}
/**
* Sets the ranges from a string representation.
*
* @param rangeList the comma separated list of ranges. The empty
* string sets the range to empty.
* @exception IllegalArgumentException if the rangeList was not well formed
*/
public void setRanges(String rangeList) {
Vector ranges = new Vector (10);
// Split the rangeList up into the vector
while (!rangeList.equals("")) {
String range = rangeList.trim();
int commaLoc = rangeList.indexOf(',');
if (commaLoc != -1) {
range = rangeList.substring(0, commaLoc).trim();
rangeList = rangeList.substring(commaLoc + 1).trim();
} else {
rangeList = "";
}
if (!range.equals("")) {
if (isValidRange(range)) {
ranges.addElement(range);
} else {
throw new IllegalArgumentException("Invalid range list at " + range
+ rangeList);
}
}
}
m_RangeStrings = ranges;
if (m_Upper >= 0) {
setFlags();
}
}
/**
* Gets whether the supplied cardinal number is included in the current
* range.
*
* @param index the number of interest
* @return true if index is in the current range
* @exception RuntimeException if the upper limit of the range hasn't been defined
*/
public boolean isInRange(int index) {
if (m_Upper == -1) {
throw new RuntimeException("No upper limit has been specified for range");
}
if (m_Invert) {
return !m_SelectFlags[index];
} else {
return m_SelectFlags[index];
}
}
/**
* Constructs a representation of the current range. Being a string
* representation, the numbers are based from 1.
*
* @return the string representation of the current range
*/
public String toString() {
if (m_RangeStrings.size() == 0) {
return "Empty";
}
String result ="Strings: ";
Enumeration enum = m_RangeStrings.elements();
while (enum.hasMoreElements()) {
result += (String)enum.nextElement() + " ";
}
result += "\n";
result += "Invert: " + m_Invert + "\n";
try {
if (m_Upper == -1) {
throw new RuntimeException("Upper limit has not been specified");
}
String cols = null;
for (int i = 0; i < m_SelectFlags.length; i++) {
if (isInRange(i)) {
if (cols == null) {
cols = "Cols: " + (i + 1);
} else {
cols += "," + (i + 1);
}
}
}
if (cols != null) {
result += cols + "\n";
}
} catch (Exception ex) {
result += ex.getMessage();
}
return result;
}
/**
* Gets an array containing all the selected values, in the order
* that they were selected (or ascending order if range inversion is on)
*
* @return the array of selected values
* @exception RuntimeException if the upper limit of the range hasn't been defined
*/
public int [] getSelection() {
if (m_Upper == -1) {
throw new RuntimeException("No upper limit has been specified for range");
}
int [] selectIndices = new int [m_Upper + 1];
int numSelected = 0;
if (m_Invert)
{
for (int i = 0; i <= m_Upper; i++) {
if (!m_SelectFlags[i]) {
selectIndices[numSelected++] = i;
}
}
}
else
{
Enumeration enum = m_RangeStrings.elements();
while (enum.hasMoreElements()) {
String currentRange = (String)enum.nextElement();
int start = rangeLower(currentRange);
int end = rangeUpper(currentRange);
for (int i = start; (i <= m_Upper) && (i <= end); i++) {
if (m_SelectFlags[i]) {
selectIndices[numSelected++] = i;
}
}
}
}
int [] result = new int [numSelected];
System.arraycopy(selectIndices, 0, result, 0, numSelected);
return result;
}
/**
* Creates a string representation of the indices in the supplied array.
*
* @param indices an array containing indices to select.
* Since the array will typically come from a program, indices are assumed
* from 0, and thus will have 1 added in the String representation.
*/
public static String indicesToRangeList(int []indices) {
StringBuffer rl = new StringBuffer();
int last = -2;
boolean range = false;
for(int i = 0; i < indices.length; i++) {
if (i == 0) {
rl.append(indices[i] + 1);
} else if (indices[i] == last) {
range = true;
} else {
if (range) {
rl.append('-').append(last);
range = false;
}
rl.append(',').append(indices[i] + 1);
}
last = indices[i] + 1;
}
if (range) {
rl.append('-').append(last);
}
return rl.toString();
}
/** Sets the flags array. */
protected void setFlags() {
m_SelectFlags = new boolean [m_Upper + 1];
Enumeration enum = m_RangeStrings.elements();
while (enum.hasMoreElements()) {
String currentRange = (String)enum.nextElement();
int start = rangeLower(currentRange);
int end = rangeUpper(currentRange);
for (int i = start; (i <= m_Upper) && (i <= end); i++) {
m_SelectFlags[i] = true;
}
}
}
/**
* Translates a single string selection into it's internal 0-based equivalent
*
* @param single the string representing the selection (eg: 1 first last)
* @return the number corresponding to the selected value
*/
protected int rangeSingle(String single) {
if (single.toLowerCase().equals("first")) {
return 0;
}
if (single.toLowerCase().equals("last")) {
return m_Upper;
}
int index = Integer.parseInt(single) - 1;
if (index < 0) {
index = 0;
}
if (index > m_Upper) {
index = m_Upper;
}
return index;
}
/**
* Translates a range into it's lower index.
*
* @param range the string representation of the range
* @return the lower index of the range
*/
protected int rangeLower(String range) {
int hyphenIndex;
if ((hyphenIndex = range.indexOf('-')) >= 0) {
return Math.min(rangeLower(range.substring(0, hyphenIndex)),
rangeLower(range.substring(hyphenIndex + 1)));
}
return rangeSingle(range);
}
/**
* Translates a range into it's upper index. Must only be called once
* setUpper has been called.
*
* @param range the string representation of the range
* @return the upper index of the range
*/
protected int rangeUpper(String range) {
int hyphenIndex;
if ((hyphenIndex = range.indexOf('-')) >= 0) {
return Math.max(rangeUpper(range.substring(0, hyphenIndex)),
rangeUpper(range.substring(hyphenIndex + 1)));
}
return rangeSingle(range);
}
/**
* Determines if a string represents a valid index or simple range.
* Examples: first last 2 first-last first-4 4-last
* Doesn't check that a < b for a-b
*
* @param range
* @return true if the range is valid
*/
protected boolean isValidRange(String range) {
if (range == null) {
return false;
}
int hyphenIndex;
if ((hyphenIndex = range.indexOf('-')) >= 0) {
if (isValidRange(range.substring(0, hyphenIndex)) &&
isValidRange(range.substring(hyphenIndex + 1))) {
return true;
}
return false;
}
if (range.toLowerCase().equals("first")) {
return true;
}
if (range.toLowerCase().equals("last")) {
return true;
}
try {
int index = Integer.parseInt(range);
if (index > 0) {
return true;
}
return false;
} catch (NumberFormatException ex) {
return false;
}
}
/**
* Main method for testing this class.
*
* @param argv one parameter: a test range specification
*/
public static void main(String [] argv) {
try {
if (argv.length == 0) {
throw new Exception("Usage: Range