string as number

README.md

@@ -200,6 +200,10 @@ mvn clean install -Pqulice
 Note: [Checkstyle](https://en.wikipedia.org/wiki/Checkstyle) is used as a static code analyze tool with
 [checks list](http://checkstyle.sourceforge.net/checks.html) in GitHub precommits.
 
+## Contributors
+
+ - [Kirill Che.](https://github.com/g4s8) [email protected]
+
 ## License (MIT)
 
 Copyright (c) 2017 Yegor Bugayenko

src/main/java/org/cactoos/text/StringAsNumber.java

@@ -0,0 +1,71 @@
+/**
+ * The MIT License (MIT)
+ *
+ * Copyright (c) 2017 Yegor Bugayenko
+ *
+ * Permission is hereby granted, free of charge, to any person obtaining a copy
+ * of this software and associated documentation files (the "Software"), to deal
+ * in the Software without restriction, including without limitation the rights
+ * to use, copy, modify, merge, publish, distribute, sublicense, and/or sell
+ * copies of the Software, and to permit persons to whom the Software is
+ * furnished to do so, subject to the following conditions:
+ *
+ * The above copyright notice and this permission notice shall be included
+ * in all copies or substantial portions of the Software.
+ *
+ * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
+ * IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
+ * FITNESS FOR A PARTICULAR PURPOSE AND NON-INFRINGEMENT. IN NO EVENT SHALL THE
+ * AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER
+ * LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM,
+ * OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE
+ * SOFTWARE.
+ */
+package org.cactoos.text;
+
+/**
+ * String as {@link Number}.
+ *
+ * @author Kirill ([email protected])
+ * @version $Id$
+ * @since 0.2
+ */
+public final class StringAsNumber extends Number {
+
+    private static final long serialVersionUID = 27917942951259451L;
+
+    /**
+     * Source string.
+     */
+    private final String string;
+
+    /**
+     * Ctor.
+     *
+     * @param string Source string
+     */
+    public StringAsNumber(final String string) {
+        super();
+        this.string = string;
+    }
+
+    @Override
+    public int intValue() {
+        return Integer.valueOf(this.string);
+    }
+
+    @Override
+    public long longValue() {
+        return Long.valueOf(this.string);
+    }
+
+    @Override
+    public float floatValue() {
+        return Float.valueOf(this.string);
+    }
+
+    @Override
+    public double doubleValue() {
+        return Double.valueOf(this.string);
+    }
+}

src/test/java/org/cactoos/text/StringAsNumberTest.java

@@ -0,0 +1,86 @@
+/**
+ * The MIT License (MIT)
+ *
+ * Copyright (c) 2017 Yegor Bugayenko
+ *
+ * Permission is hereby granted, free of charge, to any person obtaining a copy
+ * of this software and associated documentation files (the "Software"), to deal
+ * in the Software without restriction, including without limitation the rights
+ * to use, copy, modify, merge, publish, distribute, sublicense, and/or sell
+ * copies of the Software, and to permit persons to whom the Software is
+ * furnished to do so, subject to the following conditions:
+ *
+ * The above copyright notice and this permission notice shall be included
+ * in all copies or substantial portions of the Software.
+ *
+ * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
+ * IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
+ * FITNESS FOR A PARTICULAR PURPOSE AND NON-INFRINGEMENT. IN NO EVENT SHALL THE
+ * AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER
+ * LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM,
+ * OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE
+ * SOFTWARE.
+ */
+package org.cactoos.text;
+
+import org.hamcrest.MatcherAssert;
+import org.hamcrest.Matchers;
+import org.junit.Test;
+
+/**
+ * Test case for {@link StringAsNumber}.
+ *
+ * @author Kirill ([email protected])
+ * @version $Id$
+ * @since 0.2
+ */
+public final class StringAsNumberTest {
+
+    /**
+     * Test {@link Integer}.
+     */
+    @Test
+    public void intTest() {
+        MatcherAssert.assertThat(
+            new StringAsNumber("-198815458").intValue(),
+            // @checkstyle MagicNumber (1 line)
+            Matchers.equalTo(-198815458)
+        );
+    }
+
+    /**
+     * Test {@link Long}.
+     */
+    @Test
+    public void longTest() {
+        MatcherAssert.assertThat(
+            new StringAsNumber("9145723601264654").longValue(),
+            // @checkstyle MagicNumber (1 line)
+            Matchers.equalTo(9145723601264654L)
+        );
+    }
+
+    /**
+     * Test {@link Float}.
+     */
+    @Test
+    public strictfp void floatTest() {
+        MatcherAssert.assertThat(
+            new StringAsNumber("765923.24").floatValue(),
+            // @checkstyle MagicNumber (1 line)
+            Matchers.equalTo(765923.24F)
+        );
+    }
+
+    /**
+     * Test {@link Double}.
+     */
+    @Test
+    public strictfp void doubleTest() {
+        MatcherAssert.assertThat(
+            new StringAsNumber("0.25323464151").doubleValue(),
+            // @checkstyle MagicNumber (1 line)
+            Matchers.equalTo(0.25323464151)
+        );
+    }
+}