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1
52
53 package freemarker.core;
54
55 import freemarker.template.*;
56
57
62 final class ArithmeticExpression extends Expression {
63
64 static final int SUBSTRACTION = 0;
65 static final int MULTIPLICATION = 1;
66 static final int DIVISION = 2;
67 static final int MODULUS = 3;
68
69 private static final char[] OPERATORS = new char[] {'-','*','/','%'};
70
71 private final Expression left;
72 private final Expression right;
73 private final int operation;
74
75 ArithmeticExpression(Expression left, Expression right, int operation) {
76 this.left = left;
77 this.right = right;
78 this.operation = operation;
79 }
80
81 TemplateModel _getAsTemplateModel(Environment env) throws TemplateException
82 {
83 TemplateModel leftModel = left.getAsTemplateModel(env);
84 TemplateModel rightModel = right.getAsTemplateModel(env);
85 boolean leftIsNumber = (leftModel instanceof TemplateNumberModel);
86 boolean rightIsNumber = (rightModel instanceof TemplateNumberModel);
87 boolean bothNumbers = leftIsNumber && rightIsNumber;
88 if (!bothNumbers) {
89 String  msg = "Error " + getStartLocation();
90 if (!leftIsNumber) {
91 msg += "\nExpression " + left + " is not numerical";
92 }
93 if (!rightIsNumber) {
94 msg += "\nExpression " + right + " is not numerical";
95 }
96 throw new NonNumericalException(msg, env);
97 }
98 Number first = EvaluationUtil.getNumber(leftModel, left, env);
99 Number second = EvaluationUtil.getNumber(rightModel, right, env);
100 ArithmeticEngine ae =
101 env != null
102 ? env.getArithmeticEngine()
103 : getTemplate().getArithmeticEngine();
104 switch (operation) {
105 case SUBSTRACTION :
106 return new SimpleNumber(ae.subtract(first, second));
107 case MULTIPLICATION :
108 return new SimpleNumber(ae.multiply(first, second));
109 case DIVISION :
110 return new SimpleNumber(ae.divide(first, second));
111 case MODULUS :
112 return new SimpleNumber(ae.modulus(first, second));
113 default:
114 throw new TemplateException("unknown operation : " + operation, env);
115 }
116 }
117
118 public String getCanonicalForm() {
119 return left.getCanonicalForm() + ' ' + OPERATORS[operation] + ' ' + right.getCanonicalForm();
120 }
121
122 boolean isLiteral() {
123 return constantValue != null || (left.isLiteral() && right.isLiteral());
124 }
125
126 Expression _deepClone(String name, Expression subst) {
127 return new ArithmeticExpression(left.deepClone(name, subst), right.deepClone(name, subst), operation);
128 }
129 }
130 |
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