Skip to content

Commit d85757d

Browse files
umangbudhwarumangbudhwar
authored
BAEL-4695 - Evaluating a Math Expression in Java (eugenp#10345)
* Added code for checking if a class is abstract or not. * Renamed test name as per review comments. * BAEL-4695 - Added code to evaluate math expressions. * BAEL-4695 - Added test case for math function. * BAEL-4695 Added consistent examples and entry in parent pom. * BAEL-4695 - Added more examples
1 parent f7ba386 commit d85757d

3 files changed

Lines changed: 127 additions & 0 deletions

File tree

‎core-java-modules/core-java-lang-math-3/pom.xml‎

Lines changed: 35 additions & 0 deletions
Original file line numberDiff line numberDiff line change
@@ -0,0 +1,35 @@
1+
<?xml version="1.0" encoding="UTF-8"?>
2+
<project xmlns="http://maven.apache.org/POM/4.0.0"
3+
xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance"
4+
xsi:schemaLocation="http://maven.apache.org/POM/4.0.0 http://maven.apache.org/xsd/maven-4.0.0.xsd">
5+
<modelVersion>4.0.0</modelVersion>
6+
<artifactId>core-java-lang-math-3</artifactId>
7+
<version>0.0.1-SNAPSHOT</version>
8+
<name>core-java-lang-math-3</name>
9+
<parent>
10+
<groupId>com.baeldung.core-java-modules</groupId>
11+
<artifactId>core-java-modules</artifactId>
12+
<version>0.0.1-SNAPSHOT</version>
13+
<relativePath>../</relativePath>
14+
</parent>
15+
16+
<dependencies>
17+
<dependency>
18+
<groupId>net.objecthunter</groupId>
19+
<artifactId>exp4j</artifactId>
20+
<version>0.4.8</version>
21+
</dependency>
22+
23+
<dependency>
24+
<groupId>com.fathzer</groupId>
25+
<artifactId>javaluator</artifactId>
26+
<version>3.0.3</version>
27+
</dependency>
28+
</dependencies>
29+
30+
31+
<properties>
32+
33+
</properties>
34+
35+
</project>

‎core-java-modules/core-java-lang-math-3/src/test/java/com/baeldung/math/evaluate/EvalauteMathExpressionsUnitTest.java‎

Lines changed: 91 additions & 0 deletions
Original file line numberDiff line numberDiff line change
@@ -0,0 +1,91 @@
1+
package com.baeldung.math.evaluate;
2+
3+
import javax.script.ScriptEngine;
4+
import javax.script.ScriptEngineManager;
5+
import javax.script.ScriptException;
6+
7+
import org.junit.jupiter.api.Assertions;
8+
import org.junit.jupiter.api.Test;
9+
10+
import com.fathzer.soft.javaluator.DoubleEvaluator;
11+
import com.fathzer.soft.javaluator.StaticVariableSet;
12+
13+
import net.objecthunter.exp4j.Expression;
14+
import net.objecthunter.exp4j.ExpressionBuilder;
15+
16+
public class EvalauteMathExpressionsUnitTest {
17+
18+
@Test
19+
public void givenSimpleExpression_whenCallEvaluateMethod_thenSuccess() {
20+
Expression expression = new ExpressionBuilder("3+2").build();
21+
double result = expression.evaluate();
22+
Assertions.assertEquals(5, result);
23+
}
24+
25+
@Test
26+
public void givenTwoVariables_whenCallEvaluateMethod_thenSuccess() {
27+
Expression expression = new ExpressionBuilder("3x+2y").variables("x", "y")
28+
.build()
29+
.setVariable("x", 2)
30+
.setVariable("y", 3);
31+
double result = expression.evaluate();
32+
Assertions.assertEquals(12, result);
33+
}
34+
35+
@Test
36+
public void givenMathFunctions_whenCallEvaluateMethod_thenSuccess() {
37+
Expression expression = new ExpressionBuilder("sin(x)*sin(x)+cos(x)*cos(x)").variables("x")
38+
.build()
39+
.setVariable("x", 0.5);
40+
double result = expression.evaluate();
41+
Assertions.assertEquals(1, result);
42+
}
43+
44+
@Test
45+
public void givenExpression_whenCallEvaluateMethod_thenSuccess() {
46+
String expression = "3+2";
47+
DoubleEvaluator eval = new DoubleEvaluator();
48+
Double result = eval.evaluate(expression);
49+
Assertions.assertEquals(5, result);
50+
}
51+
52+
@Test
53+
public void givenVariables_whenCallEvaluateMethod_thenSuccess() {
54+
String expression = "3*x+2*y";
55+
DoubleEvaluator eval = new DoubleEvaluator();
56+
StaticVariableSet<Double> variables = new StaticVariableSet<Double>();
57+
variables.set("x", 2.0);
58+
variables.set("y", 3.0);
59+
Double result = eval.evaluate(expression, variables);
60+
Assertions.assertEquals(12, result);
61+
}
62+
63+
@Test
64+
public void givenMathFunction_whenCallEvaluateMethod_thenSuccess() {
65+
String expression = "sin(x)*sin(x)+cos(x)*cos(x)";
66+
DoubleEvaluator eval = new DoubleEvaluator();
67+
StaticVariableSet<Double> variables = new StaticVariableSet<Double>();
68+
variables.set("x", 0.5);
69+
Double result = eval.evaluate(expression, variables);
70+
Assertions.assertEquals(1, result);
71+
}
72+
73+
@Test
74+
public void givenJavaScriptingApiAndSimpleExpression_whenCallEvalMethod_thenSuccess() throws ScriptException {
75+
ScriptEngineManager scriptEngineManager = new ScriptEngineManager();
76+
ScriptEngine scriptEngine = scriptEngineManager.getEngineByName("JavaScript");
77+
String expression = "3+2";
78+
Integer result = (Integer) scriptEngine.eval(expression);
79+
Assertions.assertEquals(5, result);
80+
}
81+
82+
@Test
83+
public void givenJavaScriptingApi_whenCallEvalMethod_thenSuccess() throws ScriptException {
84+
ScriptEngineManager scriptEngineManager = new ScriptEngineManager();
85+
ScriptEngine scriptEngine = scriptEngineManager.getEngineByName("JavaScript");
86+
String expression = "x=2; y=3; 3*x+2*y;";
87+
Double result = (Double) scriptEngine.eval(expression);
88+
Assertions.assertEquals(12, result);
89+
}
90+
91+
}

‎core-java-modules/pom.xml‎

Lines changed: 1 addition & 0 deletions
Original file line numberDiff line numberDiff line change
@@ -84,6 +84,7 @@
8484
<module>core-java-lang-3</module>
8585
<module>core-java-lang-math</module>
8686
<module>core-java-lang-math-2</module>
87+
<module>core-java-lang-math-3</module>
8788
<module>core-java-lang-oop-constructors</module>
8889
<module>core-java-lang-oop-patterns</module>
8990
<module>core-java-lang-oop-generics</module>

0 commit comments

Comments
 (0)