Java Tutorial/Apache Common/toString builder

Reflection to StringBuilder

   <source lang="java">

/*

* ========================================================================
* 
* Copyright 2005 Tim O"Brien.
*
* Licensed under the Apache License, Version 2.0 (the "License");
* you may not use this file except in compliance with the License.
* You may obtain a copy of the License at
* 
*   http://www.apache.org/licenses/LICENSE-2.0
* 
* Unless required by applicable law or agreed to in writing, software
* distributed under the License is distributed on an "AS IS" BASIS,
* WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
* See the License for the specific language governing permissions and
* limitations under the License.
* 
* ========================================================================
*/

import org.apache.rumons.lang.builder.rupareToBuilder; import org.apache.rumons.lang.builder.EqualsBuilder; import org.apache.rumons.lang.builder.HashCodeBuilder; import org.apache.rumons.lang.builder.ReflectionToStringBuilder; class BuilderBean implements Comparable {

 private String prop1;
 private String prop2;
 public String getProp1() {
   return prop1;
 }
 public void setProp1(String pProp1) {
   prop1 = pProp1;
 }
 public String getProp2() {
   return prop2;
 }
 public void setProp2(String pProp2) {
   prop2 = pProp2;
 }
 public String toString() {
   return ReflectionToStringBuilder.toString(this);
 }
 public boolean equals(Object pObject) {
   return EqualsBuilder.reflectionEquals(this, pObject);
 }
 public int compareTo(Object pObject) {
   return CompareToBuilder.reflectionCompare(this, pObject);
 }
 public int hashCode() {
   return HashCodeBuilder.reflectionHashCode(this);
 }

} public class MainClass {

 public static void main(String[] pArgs) throws Exception {
   // Builder and Builder2 contain the same content
   BuilderBean builder = new BuilderBean();
   builder.setProp1("One");
   builder.setProp2("Two");
   BuilderBean builder2 = new BuilderBean();
   builder2.setProp1("One");
   builder2.setProp2("Two");
   BuilderBean builder3 = new BuilderBean();
   builder3.setProp1("Uno");
   builder3.setProp2("Dos");
   System.out.println("ToStringBuilder: " + builder.toString());
 }

}</source>

ToStringBuilder: BuilderBean@743399[prop1=One,prop2=Two]

ToStringBuilder

   <source lang="java">

/*

* ========================================================================
* 
* Copyright 2005 Tim O"Brien.
*
* Licensed under the Apache License, Version 2.0 (the "License");
* you may not use this file except in compliance with the License.
* You may obtain a copy of the License at
* 
*   http://www.apache.org/licenses/LICENSE-2.0
* 
* Unless required by applicable law or agreed to in writing, software
* distributed under the License is distributed on an "AS IS" BASIS,
* WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
* See the License for the specific language governing permissions and
* limitations under the License.
* 
* ========================================================================
*/

import java.math.BigDecimal; import java.util.HashSet; import java.util.Set; import java.math.BigDecimal; import org.apache.rumons.lang.builder.rupareToBuilder; import org.apache.rumons.lang.builder.EqualsBuilder; import org.apache.rumons.lang.builder.HashCodeBuilder; import org.apache.rumons.lang.builder.ToStringBuilder; class TaxReturn {

 private String ssn;
 private int year;
 private String lastName;
 private BigDecimal taxableIncome;
 public TaxReturn() {
 }
 public TaxReturn(String pSsn, int pYear, String pLastName, BigDecimal pTaxableIncome) {
   setSsn(pSsn);
   setYear(pYear);
   setLastName(pLastName);
   setTaxableIncome(pTaxableIncome);
 }
 public String getSsn() {
   return ssn;
 }
 public void setSsn(String pSsn) {
   ssn = pSsn;
 }
 public int getYear() {
   return year;
 }
 public void setYear(int pYear) {
   year = pYear;
 }
 public String getLastName() {
   return lastName;
 }
 public void setLastName(String pLastName) {
   lastName = pLastName;
 }
 public BigDecimal getTaxableIncome() {
   return taxableIncome;
 }
 public void setTaxableIncome(BigDecimal pTaxableIncome) {
   taxableIncome = pTaxableIncome;
 }
 public String toString() {
   return new ToStringBuilder(this).append("ssn", ssn).append("year", year).append("lastName",
       lastName).toString();
 }
 public int hashCode() {
   return new HashCodeBuilder(3, 7).append(ssn).append(year).toHashCode();
 }
 public boolean equals(Object pObject) {
   boolean equals = false;
   if (pObject instanceof TaxReturn) {
     TaxReturn bean = (TaxReturn) pObject;
     equals = (new EqualsBuilder().append(ssn, bean.ssn).append(year, bean.year)).isEquals();
   }
   return equals;
 }
 public int compareTo(Object pObject) {
   return CompareToBuilder.reflectionCompare(this, pObject);
 }

} public class MainClass {

 public static void main(String[] pArgs) throws Exception {
    TaxReturn return1 = new TaxReturn("012-68-3242", 1998, "O"Brien", new BigDecimal(43000.00));
    TaxReturn return2 = new TaxReturn("012-68-3242", 1999, "O"Brien", new BigDecimal(45000.00));
    TaxReturn return3 = new TaxReturn("012-68-3242", 1999, "O"Brien", new BigDecimal(53222.00));
    System.out.println("ToStringBuilder: " + return1.toString());
 }

}</source>

ToStringBuilder: TaxReturn@1503a3[ssn=012-68-3242,year=1998,lastName=O"Brien]

ToString Builder for Derived Class

   <source lang="java">

/*

* ========================================================================
* 
* Copyright 2005 Tim O"Brien.
*
* Licensed under the Apache License, Version 2.0 (the "License");
* you may not use this file except in compliance with the License.
* You may obtain a copy of the License at
* 
*   http://www.apache.org/licenses/LICENSE-2.0
* 
* Unless required by applicable law or agreed to in writing, software
* distributed under the License is distributed on an "AS IS" BASIS,
* WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
* See the License for the specific language governing permissions and
* limitations under the License.
* 
* ========================================================================
*/

import java.math.BigDecimal; import java.util.Calendar; import java.util.Date; import java.util.GregorianCalendar; import org.apache.rumons.lang.builder.rupareToBuilder; import org.apache.rumons.lang.builder.ReflectionToStringBuilder; import org.apache.rumons.lang.builder.ToStringBuilder; import org.apache.rumons.lang.builder.ToStringStyle; public class MainClass {

 public static void main(String[] pArgs) throws Exception {
   // Create a State
   State va = new State("VA", "Virginia");
   // Create a Birth Date
   Calendar calendar = new GregorianCalendar();
   calendar.set(Calendar.YEAR, 1743);
   calendar.set(Calendar.MONTH, Calendar.APRIL);
   calendar.set(Calendar.DAY_OF_MONTH, 13);
   Date dob = calendar.getTime();
   BigDecimal moneyRaised = new BigDecimal(293829292.93);
   // Create a Political Candidate
   PoliticalCandidate candidate = new PoliticalCandidate("Jefferson", "Thomas", dob, moneyRaised,
       va);
   System.out.println(candidate);
   // Create a Political Candidate
   PoliticalCandidate candidate2 = new PoliticalCandidate("Jefferson", "Martha", null, null, null);
   // Create a Political Candidate
   PoliticalCandidate candidate3 = new PoliticalCandidate("Jefferson", "Martha", dob, null, va);
   System.out.println("Two Jeffersons are still different (should be > 0): "
       + candidate.rupareTo(candidate2));
   System.out.println("Two Jeffersons are still different (should be < 0): "
       + candidate2.rupareTo(candidate));
   System.out.println("Two Martha Js are the same (should be zero): "
       + candidate2.rupareTo(candidate3));
 }

} class State {

 private String abbreviation;
 private String name;
 public State() {
 }
 public State(String abbreviation, String name) {
   this.abbreviation = abbreviation;
   this.name = name;
 }
 public String getAbbreviation() {
   return abbreviation;
 }
 public void setAbbreviation(String abbreviation) {
   this.abbreviation = abbreviation;
 }
 public String getName() {
   return name;
 }
 public void setName(String name) {
   this.name = name;
 }
 public String toString() {
   return ReflectionToStringBuilder.reflectionToString(this);
 }

} /*

* ========================================================================
* 
* Copyright 2005 Tim O"Brien.
* 
* Licensed under the Apache License, Version 2.0 (the "License"); you may not
* use this file except in compliance with the License. You may obtain a copy of
* the License at
* 
* http://www.apache.org/licenses/LICENSE-2.0
* 
* Unless required by applicable law or agreed to in writing, software
* distributed under the License is distributed on an "AS IS" BASIS, WITHOUT
* WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied. See the
* License for the specific language governing permissions and limitations under
* the License.
* 
* ========================================================================
*/

class PoliticalCandidate implements Comparable {

 private String lastName;
 private String firstName;
 private Date dateOfBirth;
 private BigDecimal moneyRaised;
 private State state;
 public PoliticalCandidate() {
 }
 public PoliticalCandidate(String lastName, String firstName, Date dateOfBirth,
     BigDecimal moneyRaised, State state) {
   this.lastName = lastName;
   this.firstName = firstName;
   this.dateOfBirth = dateOfBirth;
   this.moneyRaised = moneyRaised;
   this.state = state;
 }
 public String getLastName() {
   return lastName;
 }
 public void setLastName(String lastName) {
   this.lastName = lastName;
 }
 public String getFirstName() {
   return firstName;
 }
 public void setFirstName(String firstName) {
   this.firstName = firstName;
 }
 public Date getDateOfBirth() {
   return dateOfBirth;
 }
 public void setDateOfBirth(Date dateOfBirth) {
   this.dateOfBirth = dateOfBirth;
 }
 public BigDecimal getMoneyRaised() {
   return moneyRaised;
 }
 public void setMoneyRaised(BigDecimal moneyRaised) {
   this.moneyRaised = moneyRaised;
 }
 public State getState() {
   return state;
 }
 public void setState(State state) {
   this.state = state;
 }
 /*
  * public String toString() { return
  * ReflectionToStringBuilder.reflectionToString(this); }
  */
 /*
  * // get/set methods are omitted for brevity... public String toString() {
  * return new ToStringBuilder(this, ToStringStyle.MULTI_LINE_STYLE) .append(
  * "lastName", lastName ) .append( "firstName", firstName ) .toString(); }
  */
 /*
  * // get/set methods are omitted for brevity... public String toString() {
  * return new ToStringBuilder(this, ToStringStyle.DEFAULT_STYLE) .append(
  * "lastName", lastName ) .append( "firstName", firstName ) .toString(); }
  */
 /*
  * // get/set methods are omitted for brevity... public String toString() {
  * return new ToStringBuilder(this, ToStringStyle.NO_FIELD_NAMES_STYLE)
  * .append( "lastName", lastName ) .append( "firstName", firstName )
  * .toString(); }
  */
 // get/set methods are omitted for brevity...
 public String toString() {
   return new ToStringBuilder(this, ToStringStyle.SIMPLE_STYLE).append("lastName", lastName)
       .append("firstName", firstName).toString();
 }
 /*
  * (non-Javadoc)
  * 
  * @see java.lang.ruparable#compareTo(java.lang.Object)
  */
 // A compare to which mimics the behavior of equals()
 public int compareTo(Object o) {
   int compare = -1; // By default return less-than
   if (o != null && PoliticalCandidate.class.isAssignableFrom(o.getClass())) {
     PoliticalCandidate pc = (PoliticalCandidate) o;
     compare = (new CompareToBuilder().append(firstName, pc.firstName).append(lastName,
         pc.lastName)).toComparison();
   }
   return compare;
 }

}</source>

Jefferson,Thomas
Two Jeffersons are still different (should be > 0): 7
Two Jeffersons are still different (should be < 0): -7
Two Martha Js are the same (should be zero): 0

ToStringBuilder.reflectionToString

   <source lang="java">

import org.apache.rumons.lang.builder.EqualsBuilder; import org.apache.rumons.lang.builder.HashCodeBuilder; import org.apache.rumons.lang.builder.ToStringBuilder; import org.apache.rumons.lang.builder.ToStringStyle; public class MainClass {

   public static void main(String[] args) {
       MyClass one = new MyClass("Becker", 35);
       MyClass two = new MyClass("Becker", 35);
       MyClass three = new MyClass("Agassi", 33);
       System.out.println("One>>>" + one);
       System.out.println("Two>>>" + two);
       System.out.println("Three>>>" + three);
       System.out.println("one equals two? " + one.equals(two));
       System.out.println("one equals three? " + one.equals(three));
       System.out.println("One HashCode>>> " + one.hashCode());
       System.out.println("Two HashCode>>> " + two.hashCode());
       System.out.println("Three HashCode>>> " + three.hashCode());
   }

} class MyClass {

   private String name = null;
   private int age = 0;
   public MyClass(String name, int age) {
       this.name = name;
       this.age = age;
   }
   public boolean equals(Object obj) {
       return EqualsBuilder.reflectionEquals(this, obj);
   }
   public String toString() {
       return ToStringBuilder.reflectionToString(this,
           ToStringStyle.MULTI_LINE_STYLE);
   }
   public int hashCode() {
       return HashCodeBuilder.reflectionHashCode(this);
   }

}</source>

One>>>MyClass@743399[
  name=Becker
  age=35
]
Two>>>MyClass@1d8957f[
  name=Becker
  age=35
]
Three>>>MyClass@3ee284[
  name=Agassi
  age=33
]
one equals two? true
one equals three? false
One HashCode>>> 462213092
Two HashCode>>> 462213092
Three HashCode>>> -530629296

ToString Style.MULTI_LINE_STYLE

   <source lang="java">

import org.apache.rumons.lang.builder.EqualsBuilder; import org.apache.rumons.lang.builder.HashCodeBuilder; import org.apache.rumons.lang.builder.ToStringBuilder; import org.apache.rumons.lang.builder.ToStringStyle;

public class MainClass {

 public static void main(String[] args) {
   //Create new BuilderTrial instances
   BuilderTrial one = new BuilderTrial("Becker", 35);
   BuilderTrial two = new BuilderTrial("Becker", 35);
   BuilderTrial three = new BuilderTrial("Agassi", 33);
   //one and two hold the same data in different objects
   //three holds different data
   System.out.println("One>>>" + one);
   System.out.println("Two>>>" + two);
   System.out.println("Three>>>" + three);
   System.out.println("one equals two? " + one.equals(two));
   System.out.println("one equals three? " + one.equals(three));
   //As one and two hold the same data, the same hashcode is returned.
   System.out.println("One HashCode>>> " + one.hashCode());
   System.out.println("Two HashCode>>> " + two.hashCode());
   System.out.println("Three HashCode>>> " + three.hashCode());
 }

} class BuilderTrial {

 private String name;
 private int age;
 public BuilderTrial(String name, int age) {
     this.name = name;
     this.age = age;
 }
 public static void main(String[] args) {
 }
 public boolean equals(Object objCompared) {
     if (!(objCompared instanceof BuilderTrial)) {
         return false;
     }
     BuilderTrial rhs = (BuilderTrial) objCompared;
     return new EqualsBuilder().append(name, rhs.name).append(age, rhs.age)
                               .isEquals();
 }
 public String toString() {
     return new ToStringBuilder(this, ToStringStyle.MULTI_LINE_STYLE).append("Name",
         name).append("Age", age).toString();
 }
 public int hashCode() {
     return new HashCodeBuilder(15, 19).append(name).append(age).toHashCode();
 }

}</source>

One>>>BuilderTrial@a981ca[
  Name=Becker
  Age=35
]
Two>>>BuilderTrial@e7b241[
  Name=Becker
  Age=35
]
Three>>>BuilderTrial@167d940[
  Name=Agassi
  Age=33
]
one equals two? true
one equals three? false
One HashCode>>> -923455822
Two HashCode>>> -923455822
Three HashCode>>> -1433293806