setattribute.java

Boosting算法软件包

package jboost.examples;

import java.util.Arrays;

import jboost.monitor.Monitor;

/**
 * An attribute that represents a (small) subset of a large discrete
 *   set.  This attribute is used to represent the existance of a set
 *   of words in a natural-language document such as Email.
 * @author Yoram Singer */
public class SetAttribute extends Attribute {

    /** a testing main */
    public static void main(String[] argv) {
	try {
	    if(Monitor.logLevel>3) Monitor.log("starting to test SetAttribute");
	    int[] s={5,2,3,7};
	    SetAttribute a = new SetAttribute(s);
	    if(Monitor.logLevel>3) Monitor.log(a);
	    if(Monitor.logLevel>3) Monitor.log("The element 2 is in the set:  "
			       +a.contains(2));
	    if(Monitor.logLevel>3) Monitor.log("The element 4 is in the set:  "
			       +a.contains(4));
	    
	    if(Monitor.logLevel>3) Monitor.log("testing exception throwing");
	    s[0]=7;
	    try{
		a = new SetAttribute(s);
	    }
	    catch(RepeatedElementException e) {
		if(Monitor.logLevel>3) Monitor.log(e.getMessage());
	    }
	    if(Monitor.logLevel>3) Monitor.log("finished testing SetAttribute");
	}
	catch (Exception e) {
	    if(Monitor.logLevel>3) Monitor.log(e.getMessage());
	    e.printStackTrace();
	}
    }

    /** an array with all of the elements in sorted order */
    private int[] set;
    /** a pointer to the textDescription object related to this set (null if not based on text) */
    private TextDescription textDescription;

    /** Default Constructor */
    public SetAttribute() {
	defined=false;
    }

    /** Constructor that gets as input an array of token numbers
	(supposed to be without repetitions) */
    public SetAttribute(int[] s) throws RepeatedElementException {
	if(s==null) { 
	    defined=false;
	    set=null;
	} else {
	    set = s;		// initialize array
	    Arrays.sort(set);	// sort the values
	    for(int i=0; i<s.length-1; i++) {
		if(set[i]==set[i+1]) // check for repeated values
		    throw new RepeatedElementException("the value "+set[i]
						       +" appears more than once");
	    }
	    defined=true;
	}
	textDescription = null;
    }
    
    /** a constructor that also stores a pointer to the related textDescription object*/
    public SetAttribute(int[] s,TextDescription textDescription) throws RepeatedElementException {
	this(s);
	this.textDescription = textDescription;
    }
	
    public String toString() { 
	String s="";
	if(set==null) s+="null set";
	else if(set.length==0) s+="set with zero elements";
	else {
	    if(textDescription != null) {
		s += textDescription.toString(this);
	    } else {
		s = "Set("+(defined?"defined":"undef")
		    +") Sorted elements:\n"
		    +set[0];

		for(int i=1; i<set.length; i++) {
		    if((i % 10) == 0) s += "\n"; // print 10 element per line
		    s += ", " + set[i];
		} 
	    }
	}   
	return(s+"\n");
    }
    
    /** check if a particular value is in the set */
    public boolean contains(int val){
	return(defined && (Arrays.binarySearch(set,val) >= 0));
    }
    /** return the list of values in the set */
    public int[] getList(){return set;}

    /** returns a copy of the list of values in the set */
    public int[] cloneList(){
	int[] s = new int[set.length];
	for(int i=0; i<set.length; i++) s[i]=set[i];
	return(s);
    }

}