* ============LICENSE_START=======================================================
* ONAP
* ================================================================================
- * Copyright (C) 2019 AT&T Intellectual Property. All rights reserved.
+ * Copyright (C) 2019-2020 AT&T Intellectual Property. All rights reserved.
* ================================================================================
* Licensed under the Apache License, Version 2.0 (the "License");
* you may not use this file except in compliance with the License.
package org.onap.policy.common.utils.coder;
+import com.google.gson.JsonArray;
import com.google.gson.JsonElement;
+import java.io.Serializable;
/**
* Object type used by the {@link StandardCoder}. Different serialization tools have
* different "standard objects". For instance, GSON uses {@link JsonElement}. This class
* wraps that object so that it can be used without exposing the object, itself.
*/
-public class StandardCoderObject {
+public class StandardCoderObject implements Serializable {
+ private static final long serialVersionUID = 1L;
/**
* Data wrapped by this.
/**
* Gets a field's value from this object, traversing the object hierarchy.
*
- * @param fields field hierarchy
+ * @param fields field hierarchy. These may be strings, identifying fields within the
+ * object, or Integers, identifying an index within an array
* @return the field value or {@code null} if the field does not exist or is not a
* primitive
*/
- public String getString(String... fields) {
-
- /*
- * This could be relatively easily modified to allow Integer arguments, as well,
- * which would be used to specify indices within an array.
- */
+ public String getString(Object... fields) {
JsonElement jel = data;
- for (String field : fields) {
+ for (Object field : fields) {
if (jel == null) {
return null;
}
- if (jel.isJsonObject()) {
- jel = jel.getAsJsonObject().get(field);
+ if (field instanceof String) {
+ jel = getFieldFromObject(jel, field.toString());
+
+ } else if (field instanceof Integer) {
+ jel = getItemFromArray(jel, (int) field);
} else {
- return null;
+ throw new IllegalArgumentException("subscript is not a string or integer: " + field);
}
}
return (jel != null && jel.isJsonPrimitive() ? jel.getAsString() : null);
}
+
+ /**
+ * Gets an item from an object.
+ *
+ * @param element object from which to extract the item
+ * @param field name of the field from which to extract the item
+ * @return the item, or {@code null} if the element is not an object or if the field
+ * does not exist
+ */
+ protected JsonElement getFieldFromObject(JsonElement element, String field) {
+ if (!element.isJsonObject()) {
+ return null;
+ }
+
+ return element.getAsJsonObject().get(field);
+ }
+
+ /**
+ * Gets an item from an array.
+ *
+ * @param element array from which to extract the item
+ * @param index index of the item to extract
+ * @return the item, or {@code null} if the element is not an array or if the index is
+ * out of bounds
+ */
+ protected JsonElement getItemFromArray(JsonElement element, int index) {
+ if (index < 0) {
+ throw new IllegalArgumentException("subscript is invalid: " + index);
+ }
+
+ if (!element.isJsonArray()) {
+ return null;
+ }
+
+ JsonArray array = element.getAsJsonArray();
+
+ if (index >= array.size()) {
+ return null;
+ }
+
+ return array.get(index);
+ }
}
* ============LICENSE_START=======================================================
* ONAP
* ================================================================================
- * Copyright (C) 2019 AT&T Intellectual Property. All rights reserved.
+ * Copyright (C) 2019-2020 AT&T Intellectual Property. All rights reserved.
* ================================================================================
* Licensed under the Apache License, Version 2.0 (the "License");
* you may not use this file except in compliance with the License.
package org.onap.policy.common.utils.coder;
+import static org.assertj.core.api.Assertions.assertThatIllegalArgumentException;
import static org.junit.Assert.assertEquals;
import static org.junit.Assert.assertNotNull;
import static org.junit.Assert.assertNull;
private static final String PROP1 = "abc";
private static final String PROP2 = "ghi";
+ private static final Integer PROP2_INDEX = 1;
private static final String PROP2b = "jkl";
private static final String VAL1 = "def";
private static final String VAL2 = "mno";
- private static final String JSON = "{'abc':'def','ghi':{'jkl':'mno'}}".replace('\'', '"');
+ private static final String JSON = "{'abc':'def','ghi':[{},{'jkl':'mno'}]}".replace('\'', '"');
private StandardCoderObject sco;
assertEquals(VAL1, sco.getString(PROP1));
// multiple fields
- assertEquals(VAL2, sco.getString(PROP2, PROP2b));
+ assertEquals(VAL2, sco.getString(PROP2, PROP2_INDEX, PROP2b));
// not found
assertNull(sco.getString("xyz"));
// not a JSON object
assertNull(sco.getString(PROP1, PROP2));
+
+ // invalid subscript
+ assertThatIllegalArgumentException().isThrownBy(() -> sco.getString(10.0));
+ }
+
+ @Test
+ public void testGetFieldFromObject() {
+ // not an object
+ assertNull(sco.getFieldFromObject(fromJson("[]"), PROP1));
+
+ // field doesn't exist
+ assertNull(sco.getFieldFromObject(fromJson("{}"), "non-existent"));
+
+ // field exists
+ assertEquals(4, sco.getFieldFromObject(fromJson("{\"world\":4}"), "world").getAsInt());
+ }
+
+ @Test
+ public void testGetItemFromArray() {
+ // not an array
+ assertNull(sco.getItemFromArray(fromJson("{}"), 0));
+
+ // negative index
+ assertThatIllegalArgumentException().isThrownBy(() -> sco.getItemFromArray(fromJson("[]"), -1));
+
+ // index out of bounds
+ assertNull(sco.getItemFromArray(fromJson("[5]"), 1));
+ assertNull(sco.getItemFromArray(fromJson("[5]"), 2));
+
+ // index exists
+ assertEquals(6, sco.getItemFromArray(fromJson("[5,6,7]"), 1).getAsInt());
+
+ // edge case: first and last item
+ assertEquals(50, sco.getItemFromArray(fromJson("[50,60,70]"), 0).getAsInt());
+ assertEquals(700, sco.getItemFromArray(fromJson("[500,600,700]"), 2).getAsInt());
+ }
+
+ private JsonElement fromJson(String json) {
+ return gson.fromJson(json, JsonElement.class);
}
}
Code Review / policy / common.git / commitdiff