Fix for decimal separator during type conversion

- fix prevents situation when decimal
separator for default locale
is set to comma instead of dot.

Change-Id: I667682e4ed5e1d69e23ac2e82922cca024d1c467

java/monasca-common-model/src/main/java/monasca/common/model/alarm/AlarmSubExpression.java

@@ -18,14 +18,18 @@ package monasca.common.model.alarm;
 
 import java.io.Serializable;
 import java.text.DecimalFormat;
+import java.text.DecimalFormatSymbols;
+import java.util.Locale;
 
 import com.fasterxml.jackson.annotation.JsonIgnore;
+
 import org.antlr.v4.runtime.ANTLRInputStream;
 import org.antlr.v4.runtime.CommonTokenStream;
 import org.antlr.v4.runtime.ParserRuleContext;
 import org.antlr.v4.runtime.tree.ParseTreeWalker;
 
 import com.fasterxml.jackson.annotation.JsonCreator;
+
 import monasca.common.model.alarm.AlarmExpressionLexer;
 import monasca.common.model.alarm.AlarmExpressionParser;
 import monasca.common.model.metric.MetricDefinition;
@@ -46,7 +50,12 @@ public class AlarmSubExpression implements Serializable {
   private int periods;
   // Use a DecimalFormatter for threshold because the standard double format starts using scientific notation when
   // threshold is very large and that scientific notation can't be parsed when recreating the SubExpression
-  private static final DecimalFormat formatter = new DecimalFormat("0.0##############");
+  private static final DecimalFormat formatter;
+  static {
+    formatter = new DecimalFormat("0.0##############");
+    // Prevents situation when decimal separator for default locale is different then dot.
+    formatter.setDecimalFormatSymbols(DecimalFormatSymbols.getInstance(Locale.US));
+  }
 
   public AlarmSubExpression(AggregateFunction function, MetricDefinition metricDefinition,
       AlarmOperator operator, double threshold, int period, int periods) {

java/monasca-common-model/src/test/java/monasca/common/model/alarm/AlarmSubExpressionLocaleTest.java

@@ -0,0 +1,64 @@
+/*
+ * Copyright 2015 FUJITSU LIMITED
+ *
+ * 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
+ *
+ * http://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 monasca.common.model.alarm;
+
+import static org.testng.Assert.assertEquals;
+
+import java.util.List;
+import java.util.Locale;
+
+import org.testng.annotations.Test;
+
+import com.google.common.collect.ImmutableMap;
+import com.google.common.collect.Lists;
+
+import monasca.common.model.metric.MetricDefinition;
+
+/**
+ * Checks if conversion from decimal to string is Locale independent.
+ *
+ * @author lukasz.zajaczkowski@ts.fujitsu.com
+ *
+ */
+@Test
+public class AlarmSubExpressionLocaleTest {
+
+  private static final String EXPECTED_EXPRESSION = "min(hpcs.compute{instance_id=5, metric_name=cpu, device=1}) < 1.2";
+
+  public void shouldBeLocaleIndependent() {
+    List<Locale> localeList = Lists.newArrayList(
+        Locale.GERMAN, Locale.CHINA, Locale.FRANCE, Locale.JAPAN, Locale.CANADA, Locale.KOREA
+        );
+
+    for (Locale locale : localeList) {
+      Locale.setDefault(locale);
+      AlarmSubExpression alarmSubExpression =
+          new AlarmSubExpression(AggregateFunction.MIN, new MetricDefinition("hpcs.compute", ImmutableMap.<String, String>builder()
+              .put("instance_id", "5").put("metric_name", "cpu").put("device", "1").build()), AlarmOperator.LT, 1.2, 60, 1);
+
+      assertEquals(alarmSubExpression.getExpression(), EXPECTED_EXPRESSION, "Not correct expression for locale " + locale.getDisplayName());
+
+    }
+  }
+
+  public void shouldWorkWithDefaultLocale() {
+
+    Locale.setDefault(Locale.US);
+    AlarmSubExpression alarmSubExpression =
+        new AlarmSubExpression(AggregateFunction.MIN, new MetricDefinition("hpcs.compute", ImmutableMap.<String, String>builder()
+            .put("instance_id", "5").put("metric_name", "cpu").put("device", "1").build()), AlarmOperator.LT, 1.2, 60, 1);
+
+    assertEquals(alarmSubExpression.getExpression(), EXPECTED_EXPRESSION, "Not correct expression for default locale");
+  }
+}