Rewriting to java (#1131)

* Rewritting to java

- rewritten a lot of Spring Cloud Contract Spec module to Java
- extracted all Groovy stuff to a separate package
- will now continue writing extension modules
- spring-cloud-contract-spec will be written purely in java
- spring-cloud-contract-spec-groovy will have Groovy extensions

fixes gh-1130

specs/spring-cloud-contract-spec-java/src/test/groovy/repackaged/nl/flotsam/xeger/XegerTest.java

@@ -0,0 +1,107 @@
+/**
+ * Copyright 2009 Wilfred Springer
+ * Copyright 2012 Jason Pell
+ * Copyright 2013 Antonio García-Domínguez
+ *
+ * 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
+ *
+ *     https://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.
+ */
+
+package repackaged.nl.flotsam.xeger;
+
+import java.util.ArrayList;
+import java.util.List;
+import java.util.Random;
+
+import org.junit.Test;
+
+import static org.junit.Assert.assertEquals;
+import static org.junit.Assert.assertTrue;
+
+public class XegerTest {
+
+	@Test
+	public void shouldGenerateTextCorrectly() {
+		String regex = "[ab]{4,6}c";
+		Xeger generator = new Xeger(regex);
+		for (int i = 0; i < 100; i++) {
+			String text = generator.generate();
+			assertTrue(text.matches(regex));
+		}
+	}
+
+	@Test
+	public void shouldNotGenerateMoreThanTheLimit() {
+		String regex = "[ab]{5}";
+		Xeger.ITERATION_LIMIT = 1;
+		Xeger generator = new Xeger(regex);
+		for (int i = 0; i < 100; i++) {
+			String text = generator.generate();
+			assertTrue(text.length() == 1);
+		}
+	}
+
+	@Test
+	public void shouldGenerateTextCorrectlyForDigitSign() {
+		String regex = "\\d+";
+		Xeger generator = new Xeger(regex);
+		for (int i = 0; i < 100; i++) {
+			String text = generator.generate();
+			assertTrue(text.matches(regex));
+		}
+	}
+
+	@Test
+	public void shouldGenerateTextCorrectlyForWordSign() {
+		String regex = "\\w+";
+		Xeger generator = new Xeger(regex);
+		for (int i = 0; i < 100; i++) {
+			String text = generator.generate();
+			assertTrue(text.matches(regex));
+		}
+	}
+
+	@Test
+	public void shouldGenerateTextCorrectlyForWhiteSpaceSign() {
+		String regex = "\\s+";
+		Xeger generator = new Xeger(regex);
+		for (int i = 0; i < 100; i++) {
+			String text = generator.generate();
+			assertTrue(text.matches(regex));
+		}
+	}
+
+	@Test
+	public void testRepeatableRegex() {
+		for (int x = 0; x < 1000; x++) {
+			Xeger generator = new Xeger("[ab]{4,6}c", new Random(1000));
+			Xeger generator2 = new Xeger("[ab]{4,6}c", new Random(1000));
+
+			List<String> firstRegexList = generateRegex(generator, 100);
+			List<String> secondRegexList = generateRegex(generator2, 100);
+
+			for (int i = 0; i < firstRegexList.size(); i++) {
+				assertEquals("Index mismatch: " + i, firstRegexList.get(i),
+						secondRegexList.get(i));
+			}
+		}
+	}
+
+	private List<String> generateRegex(Xeger generator, int count) {
+		List<String> regexList = new ArrayList<>();
+		for (int i = 0; i < count; i++) {
+			regexList.add(generator.generate());
+		}
+		return regexList;
+	}
+
+}

specs/spring-cloud-contract-spec-java/src/test/groovy/repackaged/nl/flotsam/xeger/XegerUtilsTest.java

@@ -0,0 +1,40 @@
+/**
+ * Copyright 2009 Wilfred Springer
+ * Copyright 2012 Jason Pell
+ * Copyright 2013 Antonio García-Domínguez
+ * <p>
+ * 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
+ * <p>
+ * https://www.apache.org/licenses/LICENSE-2.0
+ * <p>
+ * 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.
+ */
+
+package repackaged.nl.flotsam.xeger;
+
+import java.util.Random;
+
+import org.hamcrest.Matchers;
+import org.junit.Test;
+
+import static org.junit.Assert.assertThat;
+
+public class XegerUtilsTest {
+
+	@Test
+	public void shouldGenerateRandomNumberCorrectly() {
+		Random random = new Random();
+		for (int i = 0; i < 100; i++) {
+			int number = Xeger.getRandomInt(3, 7, random);
+			assertThat(number, Matchers.greaterThanOrEqualTo(3));
+			assertThat(number, Matchers.lessThanOrEqualTo(7));
+		}
+	}
+
+}