Custom Predicate
package com.googelcode.jpractices;
import java.io.Serializable;
import org.apache.commons.collections.Predicate;
/**
* Copyright 2009 @ jPractices v 1.0
* @SVN URL : http://jpractices.googlecode.com
* @author Ganesh Gowtham
* @Homepage : http://ganesh.gowtham.googlepages.com
* @description This Predicate is responsible in selecting the salary greater than iValue
*/
public class SalaryHighPredicate implements Predicate, Serializable {
/** Serial version UID */
private static final long serialVersionUID = 5633766978029907089L;
/** The value to compare to */
private final int iValue;
public SalaryHighPredicate(int salary) {
super();
iValue = salary;
}
/**
* returns true when the salary is >= iValue
*/
public boolean evaluate(Object object) {
if (object instanceof Integer) {
//System.err.println("oops");
int value = Integer.parseInt(object.toString());
return iValue <= value ? true : false;
} else {
// worst case wont happend :-)
System.err.println("pls check whether passed attribute type");
return false;
}
}
}
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package com.googelcode.jpractices;
import java.util.ArrayList;
import java.util.Collection;
import java.util.List;
import org.apache.commons.beanutils.BeanPredicate;
import org.apache.commons.collections.CollectionUtils;
import com.googelcode.jpractices.common.Person;
/**
* Copyright 2009 @ jPractices v 1.0
* @SVN URL : http://jpractices.googlecode.com
* @author Ganesh Gowtham
* @Homepage : http://ganesh.gowtham.googlepages.com
* @Description : Writing the own predicate to filter the person objects whose salary is
* greater than 26000
*/
public class CustomPredicateExample {
List<Person> personList = new ArrayList<Person>();
/**
* Basic method which creates the list of person object's
*/
void setUpData() {
personList.add(new Person("ganesh", "gowtham", 25000));
personList.add(new Person("britney", "spears", 45000));
personList.add(new Person("ganesh", "tom", 35000));
personList.add(new Person("sunny", "dummy", 45000));
}
void filterCollection(int salary)
{
SalaryHighPredicate nameEqlPredicate = new SalaryHighPredicate(salary);
BeanPredicate beanPredicate = new BeanPredicate("salary", nameEqlPredicate);
Collection<Person> filteredCollection = CollectionUtils
.select(personList, beanPredicate);
System.out.println("Shows the person object whose salary is >= 26,000 ");
for (Person person : filteredCollection) {
System.out.println(person);
}
}
public static void main(String[] args) {
CustomPredicateExample example = new CustomPredicateExample();
example.setUpData();
example.filterCollection(26000);
}
}
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package com.googelcode.jpractices.common;
import org.apache.commons.lang.builder.ToStringBuilder;
/**
* Copyright 2009 @ jPractices v 1.0
* @SVN URL : http://jpractices.googlecode.com
* @author Ganesh Gowtham
* @Homepage : http://ganesh.gowtham.googlepages.com
*/
public class Person {
private String firstName;
private String lastName;
private int salary;
public Person(String firstName, String lastName, int salary) {
super();
this.firstName = firstName;
this.lastName = lastName;
this.salary = salary;
}
public String getFirstName() {
return firstName;
}
public void setFirstName(String firstName) {
this.firstName = firstName;
}
public String getLastName() {
return lastName;
}
public void setLastName(String lastName) {
this.lastName = lastName;
}
public int getSalary() {
return salary;
}
public void setSalary(int salary) {
this.salary = salary;
}
@Override
public String toString() {
return ToStringBuilder.reflectionToString(this);
}
}
predicate_example1.zip( 811 k)Related examples in the same category
