Fix quality flaws

3 files changed, 120 insertions, 0 deletions

diff --git a/sonar-core/src/main/java/org/sonar/core/util/NonNullInputFunction.java b/sonar-core/src/main/java/org/sonar/core/util/NonNullInputFunction.java
new file mode 100644
index 00000000000..bf312d68d25
--- /dev/null
+++ b/sonar-core/src/main/java/org/sonar/core/util/NonNullInputFunction.java
@@ -0,0 +1,44 @@
+/*
+ * SonarQube, open source software quality management tool.
+ * Copyright (C) 2008-2014 SonarSource
+ * mailto:contact AT sonarsource DOT com
+ *
+ * SonarQube is free software; you can redistribute it and/or
+ * modify it under the terms of the GNU Lesser General Public
+ * License as published by the Free Software Foundation; either
+ * version 3 of the License, or (at your option) any later version.
+ *
+ * SonarQube is distributed in the hope that it will be useful,
+ * but WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
+ * Lesser General Public License for more details.
+ *
+ * You should have received a copy of the GNU Lesser General Public License
+ * along with this program; if not, write to the Free Software Foundation,
+ * Inc., 51 Franklin Street, Fifth Floor, Boston, MA  02110-1301, USA.
+ */
+package org.sonar.core.util;
+
+import com.google.common.base.Function;
+import com.google.common.base.Preconditions;
+
+import javax.annotation.Nullable;
+
+/**
+ * Guava Function that does not accept null input elements
+ * @since 5.1
+ */
+public abstract class NonNullInputFunction<F,T> implements Function<F, T> {
+
+  @Override
+  public final T apply(@Nullable F input) {
+    Preconditions.checkNotNull(input, "Null inputs are not allowed in this function");
+    return doApply(input);
+  }
+
+  /**
+   * This method is the same as {@link #apply(Object)} except that the input argument
+   * is not marked as nullable
+   */
+  protected abstract T doApply(F input);
+}
diff --git a/sonar-core/src/main/java/org/sonar/core/util/package-info.java b/sonar-core/src/main/java/org/sonar/core/util/package-info.java
new file mode 100644
index 00000000000..5f2ad77c297
--- /dev/null
+++ b/sonar-core/src/main/java/org/sonar/core/util/package-info.java
@@ -0,0 +1,24 @@
+/*
+ * SonarQube, open source software quality management tool.
+ * Copyright (C) 2008-2014 SonarSource
+ * mailto:contact AT sonarsource DOT com
+ *
+ * SonarQube is free software; you can redistribute it and/or
+ * modify it under the terms of the GNU Lesser General Public
+ * License as published by the Free Software Foundation; either
+ * version 3 of the License, or (at your option) any later version.
+ *
+ * SonarQube is distributed in the hope that it will be useful,
+ * but WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
+ * Lesser General Public License for more details.
+ *
+ * You should have received a copy of the GNU Lesser General Public License
+ * along with this program; if not, write to the Free Software Foundation,
+ * Inc., 51 Franklin Street, Fifth Floor, Boston, MA  02110-1301, USA.
+ */
+
+@ParametersAreNonnullByDefault
+package org.sonar.core.util;
+
+import javax.annotation.ParametersAreNonnullByDefault;
diff --git a/sonar-core/src/test/java/org/sonar/core/util/NonNullInputFunctionTest.java b/sonar-core/src/test/java/org/sonar/core/util/NonNullInputFunctionTest.java
new file mode 100644
index 00000000000..f7417d0ce48
--- /dev/null
+++ b/sonar-core/src/test/java/org/sonar/core/util/NonNullInputFunctionTest.java
@@ -0,0 +1,52 @@
+/*
+ * SonarQube, open source software quality management tool.
+ * Copyright (C) 2008-2014 SonarSource
+ * mailto:contact AT sonarsource DOT com
+ *
+ * SonarQube is free software; you can redistribute it and/or
+ * modify it under the terms of the GNU Lesser General Public
+ * License as published by the Free Software Foundation; either
+ * version 3 of the License, or (at your option) any later version.
+ *
+ * SonarQube is distributed in the hope that it will be useful,
+ * but WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
+ * Lesser General Public License for more details.
+ *
+ * You should have received a copy of the GNU Lesser General Public License
+ * along with this program; if not, write to the Free Software Foundation,
+ * Inc., 51 Franklin Street, Fifth Floor, Boston, MA  02110-1301, USA.
+ */
+package org.sonar.core.util;
+
+import org.junit.Test;
+
+import static org.assertj.core.api.Assertions.assertThat;
+import static org.junit.Assert.fail;
+
+public class NonNullInputFunctionTest {
+
+  NonNullInputFunction<String, Integer> sut = new TestFunction();
+
+  @Test
+  public void fail_if_null_input() throws Exception {
+    try {
+      sut.apply(null);
+      fail();
+    } catch (NullPointerException e) {
+      assertThat(e).hasMessage("Null inputs are not allowed in this function");
+    }
+  }
+
+  @Test
+  public void apply() throws Exception {
+    assertThat(sut.apply("foo")).isEqualTo(3);
+  }
+
+  private static class TestFunction extends NonNullInputFunction<String,Integer> {
+    @Override
+    protected Integer doApply(String input) {
+      return input.length();
+    }
+  }
+}