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Merge pull request #281 from ankurkaushal/master

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Reformat according to google style guide
This commit is contained in:
Ilkka Seppälä
2015-11-02 21:39:17 +02:00
parent 7e4f04602e 306b1f3d31
commit fe63c9cec4
438 changed files with 8257 additions and 8382 deletions
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69
memento/src/main/java/com/iluwatar/memento/App.java
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@ -4,46 +4,45 @@ import java.util.Stack;
/**
*
* The Memento pattern is a software design pattern that provides the ability to restore
* an object to its previous state (undo via rollback).
* The Memento pattern is a software design pattern that provides the ability to restore an object
* to its previous state (undo via rollback).
* <p>
* The Memento pattern is implemented with three objects: the originator, a caretaker and
* a memento. The originator is some object that has an internal state. The caretaker is
* going to do something to the originator, but wants to be able to undo the change. The
* caretaker first asks the originator for a memento object. Then it does whatever operation
* (or sequence of operations) it was going to do. To roll back to the state before the
* operations, it returns the memento object to the originator. The memento object itself
* is an opaque object (one which the caretaker cannot, or should not, change). When using
* this pattern, care should be taken if the originator may change other objects or
* resources - the memento pattern operates on a single object.
* The Memento pattern is implemented with three objects: the originator, a caretaker and a memento.
* The originator is some object that has an internal state. The caretaker is going to do something
* to the originator, but wants to be able to undo the change. The caretaker first asks the
* originator for a memento object. Then it does whatever operation (or sequence of operations) it
* was going to do. To roll back to the state before the operations, it returns the memento object
* to the originator. The memento object itself is an opaque object (one which the caretaker cannot,
* or should not, change). When using this pattern, care should be taken if the originator may
* change other objects or resources - the memento pattern operates on a single object.
* <p>
* In this example the object ({@link Star})
* gives out a "memento" ({@link StarMemento}) that contains the state of the object.
* Later on the memento can be set back to the object restoring the state.
* In this example the object ({@link Star}) gives out a "memento" ({@link StarMemento}) that
* contains the state of the object. Later on the memento can be set back to the object restoring
* the state.
*
*/
public class App {
public static void main(String[] args) {
Stack<StarMemento> states = new Stack<>();
public static void main(String[] args) {
Stack<StarMemento> states = new Stack<>();
Star star = new Star(StarType.SUN, 10000000, 500000);
System.out.println(star);
states.add(star.getMemento());
star.timePasses();
System.out.println(star);
states.add(star.getMemento());
star.timePasses();
System.out.println(star);
states.add(star.getMemento());
star.timePasses();
System.out.println(star);
states.add(star.getMemento());
star.timePasses();
System.out.println(star);
while (states.size() > 0) {
star.setMemento(states.pop());
System.out.println(star);
}
}
Star star = new Star(StarType.SUN, 10000000, 500000);
System.out.println(star);
states.add(star.getMemento());
star.timePasses();
System.out.println(star);
states.add(star.getMemento());
star.timePasses();
System.out.println(star);
states.add(star.getMemento());
star.timePasses();
System.out.println(star);
states.add(star.getMemento());
star.timePasses();
System.out.println(star);
while (states.size() > 0) {
star.setMemento(states.pop());
System.out.println(star);
}
}
}

157
memento/src/main/java/com/iluwatar/memento/Star.java
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@ -7,99 +7,98 @@ package com.iluwatar.memento;
*/
public class Star {
private StarType type;
private int ageYears;
private int massTons;
private StarType type;
private int ageYears;
private int massTons;
public Star(StarType startType, int startAge, int startMass) {
this.type = startType;
this.ageYears = startAge;
this.massTons = startMass;
}
public Star(StarType startType, int startAge, int startMass) {
this.type = startType;
this.ageYears = startAge;
this.massTons = startMass;
}
public void timePasses() {
ageYears *= 2;
massTons *= 8;
switch (type) {
case RED_GIANT:
type = StarType.WHITE_DWARF;
break;
case SUN:
type = StarType.RED_GIANT;
break;
case SUPERNOVA:
type = StarType.DEAD;
break;
case WHITE_DWARF:
type = StarType.SUPERNOVA;
break;
case DEAD:
ageYears *= 2;
massTons = 0;
break;
default:
break;
}
}
public void timePasses() {
ageYears *= 2;
massTons *= 8;
switch (type) {
case RED_GIANT:
type = StarType.WHITE_DWARF;
break;
case SUN:
type = StarType.RED_GIANT;
break;
case SUPERNOVA:
type = StarType.DEAD;
break;
case WHITE_DWARF:
type = StarType.SUPERNOVA;
break;
case DEAD:
ageYears *= 2;
massTons = 0;
break;
default:
break;
}
}
StarMemento getMemento() {
StarMemento getMemento() {
StarMementoInternal state = new StarMementoInternal();
state.setAgeYears(ageYears);
state.setMassTons(massTons);
state.setType(type);
return state;
StarMementoInternal state = new StarMementoInternal();
state.setAgeYears(ageYears);
state.setMassTons(massTons);
state.setType(type);
return state;
}
}
void setMemento(StarMemento memento) {
void setMemento(StarMemento memento) {
StarMementoInternal state = (StarMementoInternal) memento;
this.type = state.getType();
this.ageYears = state.getAgeYears();
this.massTons = state.getMassTons();
StarMementoInternal state = (StarMementoInternal) memento;
this.type = state.getType();
this.ageYears = state.getAgeYears();
this.massTons = state.getMassTons();
}
}
@Override
public String toString() {
return String.format("%s age: %d years mass: %d tons", type.toString(),
ageYears, massTons);
}
/**
*
* StarMemento implementation
*
*/
private static class StarMementoInternal implements StarMemento {
@Override
public String toString() {
return String.format("%s age: %d years mass: %d tons", type.toString(), ageYears, massTons);
}
private StarType type;
private int ageYears;
private int massTons;
/**
*
* StarMemento implementation
*
*/
private static class StarMementoInternal implements StarMemento {
public StarType getType() {
return type;
}
private StarType type;
private int ageYears;
private int massTons;
public void setType(StarType type) {
this.type = type;
}
public StarType getType() {
return type;
}
public int getAgeYears() {
return ageYears;
}
public void setType(StarType type) {
this.type = type;
}
public void setAgeYears(int ageYears) {
this.ageYears = ageYears;
}
public int getAgeYears() {
return ageYears;
}
public int getMassTons() {
return massTons;
}
public void setAgeYears(int ageYears) {
this.ageYears = ageYears;
}
public void setMassTons(int massTons) {
this.massTons = massTons;
}
}
public int getMassTons() {
return massTons;
}
public void setMassTons(int massTons) {
this.massTons = massTons;
}
}
}

19
memento/src/main/java/com/iluwatar/memento/StarType.java
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@ -7,16 +7,17 @@ package com.iluwatar.memento;
*/
public enum StarType {
SUN("sun"), RED_GIANT("red giant"), WHITE_DWARF("white dwarf"), SUPERNOVA("supernova"), DEAD("dead star"), UNDEFINED("");
SUN("sun"), RED_GIANT("red giant"), WHITE_DWARF("white dwarf"), SUPERNOVA("supernova"), DEAD(
"dead star"), UNDEFINED("");
private String title;
private String title;
StarType(String title) {
this.title = title;
}
StarType(String title) {
this.title = title;
}
@Override
public String toString() {
return title;
}
@Override
public String toString() {
return title;
}
}

10
memento/src/test/java/com/iluwatar/memento/AppTest.java
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@ -11,9 +11,9 @@ import com.iluwatar.memento.App;
*/
public class AppTest {
@Test
public void test() {
String[] args = {};
App.main(args);
}
@Test
public void test() {
String[] args = {};
App.main(args);
}
}