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Formatted all files to the same standard

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This commit is contained in:
matthew
2014-10-08 13:42:12 +01:00
parent 53a2a8b150
commit 3da9ad5469
151 changed files with 952 additions and 870 deletions
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110
interpreter/src/main/java/com/iluwatar/App.java
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@ -3,64 +3,70 @@ package com.iluwatar;
import java.util.Stack;
/**
*
*
* Interpreter pattern breaks sentences into expressions (Expression) that can
* be evaluated and as a whole form the result.
*
*
*/
public class App {
/**
*
* Expressions can be evaluated using prefix, infix or postfix notations
* This sample uses postfix, where operator comes after the operands
*
*/
public static void main(String[] args) {
String tokenString = "4 3 2 - 1 + *";
Stack<Expression> stack = new Stack<>();
/**
*
* Expressions can be evaluated using prefix, infix or postfix notations
* This sample uses postfix, where operator comes after the operands
*
*/
public static void main(String[] args) {
String tokenString = "4 3 2 - 1 + *";
Stack<Expression> stack = new Stack<>();
String[] tokenList = tokenString.split(" ");
for (String s : tokenList) {
if (isOperator(s)) {
Expression rightExpression = stack.pop();
Expression leftExpression = stack.pop();
System.out.println(String.format("popped from stack left: %d right: %d",
leftExpression.interpret(), rightExpression.interpret()));
Expression operator = getOperatorInstance(s, leftExpression,
rightExpression);
System.out.println(String.format("operator: %s", operator));
int result = operator.interpret();
NumberExpression resultExpression = new NumberExpression(result);
stack.push(resultExpression);
System.out.println(String.format("push result to stack: %d", resultExpression.interpret()));
} else {
Expression i = new NumberExpression(s);
stack.push(i);
System.out.println(String.format("push to stack: %d", i.interpret()));
}
}
System.out.println(String.format("result: %d", stack.pop().interpret()));
}
String[] tokenList = tokenString.split(" ");
for (String s : tokenList) {
if (isOperator(s)) {
Expression rightExpression = stack.pop();
Expression leftExpression = stack.pop();
System.out
.println(String.format(
"popped from stack left: %d right: %d",
leftExpression.interpret(),
rightExpression.interpret()));
Expression operator = getOperatorInstance(s, leftExpression,
rightExpression);
System.out.println(String.format("operator: %s", operator));
int result = operator.interpret();
NumberExpression resultExpression = new NumberExpression(result);
stack.push(resultExpression);
System.out.println(String.format("push result to stack: %d",
resultExpression.interpret()));
} else {
Expression i = new NumberExpression(s);
stack.push(i);
System.out.println(String.format("push to stack: %d",
i.interpret()));
}
}
System.out
.println(String.format("result: %d", stack.pop().interpret()));
}
public static boolean isOperator(String s) {
if (s.equals("+") || s.equals("-") || s.equals("*")) {
return true;
} else {
return false;
}
}
public static boolean isOperator(String s) {
if (s.equals("+") || s.equals("-") || s.equals("*")) {
return true;
} else {
return false;
}
}
public static Expression getOperatorInstance(String s, Expression left,
Expression right) {
switch (s) {
case "+":
return new PlusExpression(left, right);
case "-":
return new MinusExpression(left, right);
case "*":
return new MultiplyExpression(left, right);
}
return null;
}
public static Expression getOperatorInstance(String s, Expression left,
Expression right) {
switch (s) {
case "+":
return new PlusExpression(left, right);
case "-":
return new MinusExpression(left, right);
case "*":
return new MultiplyExpression(left, right);
}
return null;
}
}

2
interpreter/src/main/java/com/iluwatar/Expression.java
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@ -3,7 +3,7 @@ package com.iluwatar;
public abstract class Expression {
public abstract int interpret();
@Override
public abstract String toString();
}

2
interpreter/src/main/java/com/iluwatar/MinusExpression.java
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@ -9,7 +9,7 @@ public class MinusExpression extends Expression {
this.leftExpression = leftExpression;
this.rightExpression = rightExpression;
}
@Override
public int interpret() {
return leftExpression.interpret() - rightExpression.interpret();

5
interpreter/src/main/java/com/iluwatar/MultiplyExpression.java
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@ -5,11 +5,12 @@ public class MultiplyExpression extends Expression {
private Expression leftExpression;
private Expression rightExpression;
public MultiplyExpression(Expression leftExpression, Expression rightExpression) {
public MultiplyExpression(Expression leftExpression,
Expression rightExpression) {
this.leftExpression = leftExpression;
this.rightExpression = rightExpression;
}
@Override
public int interpret() {
return leftExpression.interpret() * rightExpression.interpret();

4
interpreter/src/main/java/com/iluwatar/NumberExpression.java
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@ -7,11 +7,11 @@ public class NumberExpression extends Expression {
public NumberExpression(int number) {
this.number = number;
}
public NumberExpression(String s) {
this.number = Integer.parseInt(s);
}
@Override
public int interpret() {
return number;

2
interpreter/src/main/java/com/iluwatar/PlusExpression.java
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@ -9,7 +9,7 @@ public class PlusExpression extends Expression {
this.leftExpression = leftExpression;
this.rightExpression = rightExpression;
}
@Override
public int interpret() {
return leftExpression.interpret() + rightExpression.interpret();