package org.onap.appc.util;
-import com.fasterxml.jackson.databind.ObjectMapper;
-
+import java.io.FileNotFoundException;
import java.io.IOException;
+import java.io.InputStream;
import java.util.Map;
-
+import com.fasterxml.jackson.annotation.JsonInclude;
+import com.fasterxml.jackson.core.JsonParser;
+import com.fasterxml.jackson.databind.DeserializationFeature;
+import com.fasterxml.jackson.databind.ObjectMapper;
+import com.fasterxml.jackson.databind.SerializationFeature;
public class JsonUtil {
+
+ static ObjectMapper MAPPER = null;
+ static {
+ MAPPER = new ObjectMapper();
+ MAPPER.enable(SerializationFeature.INDENT_OUTPUT);
+ MAPPER.configure(JsonParser.Feature.ALLOW_COMMENTS, true);
+ MAPPER.setSerializationInclusion(JsonInclude.Include.NON_NULL);
+ MAPPER.disable(DeserializationFeature.FAIL_ON_UNKNOWN_PROPERTIES); // allow translation even
+ // if extra attrs exist
+ // in the json
+ MAPPER.configure(SerializationFeature.FAIL_ON_EMPTY_BEANS, false);
+ // Uncomment below when Jackson is upgraded to version 2.7 or above
+ // MAPPER.setPropertyNamingStrategy(PropertyNamingStrategy.KEBAB_CASE);
+ }
+
/**
* @param valueAsString a valid json Map represented as String
- * @return a flat map that each entry key derived from hierarchy path in the json object and flatted to a dotted separated string.
- * e.g. "{\"A\":\"A-value\",\"B\":{\"C\":\"B.C-value\",\"D\":\"B.D-value\"}}"; will be represented as {A=A-value, B.C=B.C-value, B.D=B.D-value}
- * when it required that the input will not be flatted the json string should be formatted as below example:
- * e.g. "{\"A\":\"A-value\",\"B\":\"{\\\"C\\\":\\\"C-value\\\",\\\"D\\\":\\\"D-value\\\"}\"}" will be represented as {A=A-value, B={"C":"C-value","D":"D-value"}}
+ * @return a flat map that each entry key derived from hierarchy path in the json object and
+ * flatted to a dotted separated string. e.g.
+ * "{\"A\":\"A-value\",\"B\":{\"C\":\"B.C-value\",\"D\":\"B.D-value\"}}"; will be
+ * represented as {A=A-value, B.C=B.C-value, B.D=B.D-value} when it required that the
+ * input will not be flatted the json string should be formatted as below example: e.g.
+ * "{\"A\":\"A-value\",\"B\":\"{\\\"C\\\":\\\"C-value\\\",\\\"D\\\":\\\"D-value\\\"}\"}"
+ * will be represented as {A=A-value, B={"C":"C-value","D":"D-value"}}
* @throws IOException when the object is not valid json Map
*/
- public static Map<String, String> convertJsonStringToFlatMap(String valueAsString) throws IOException {
- ObjectMapper objectMapper = new ObjectMapper();
- Map readValueMap = objectMapper.readValue(valueAsString,Map.class);
+ public static Map<String, String> convertJsonStringToFlatMap(String valueAsString)
+ throws IOException {
+ Map readValueMap = MAPPER.readValue(valueAsString, Map.class);
return org.onap.appc.util.ObjectMapper.map(readValueMap);
}
+
+ /**
+ * 0 is the getStackTrace method 1 is the current method 2 is the parent method, 3 is the
+ * grandparent method or the parent class in this case.
+ */
+ private static final int PARENT_CLASS_INDEX = 3;
+
+
+ /**
+ * @see #readInputJson(String, Class, Class)
+ */
+ public static <T> T readInputJson(String location, Class<T> returnClass) throws IOException {
+ return readInputJson(location, returnClass, getCallingClass(PARENT_CLASS_INDEX));
+ }
+
+ /**
+ * @param location The location or name of the file we are trying to read e.g. JsonBody.json
+ * @param returnClass The class *this* Json is suppose to represent.
+ * @param locationClass The starting point for json lookup. the value specified by location is
+ * relative to this class.
+ * @return The object being returned
+ * @throws IOException Can't find the specified json file at Location.
+ */
+ public static <T> T readInputJson(String location, Class<T> returnClass, Class<?> locationClass)
+ throws IOException {
+ try (InputStream is = locationClass.getResourceAsStream(location)) {
+ validateInput(is, location);
+ return MAPPER.readValue(is, returnClass);
+ }
+ }
+
+ /**
+ * Note that this method is sensitive to the depth of the call stack. For example if a public
+ * method calls a private method, that calls this method likely the desired classIndex value is
+ * 4 rather than 3. However, it's convenient to reduce the input required by callers of this
+ * class.
+ *
+ * @param classIndex How far up the stack trace to find the class we want.
+ * @return The class that called one of the public methods of this class.
+ */
+ private static Class<?> getCallingClass(int classIndex) {
+ String className = Thread.currentThread().getStackTrace()[classIndex].getClassName();
+ try {
+ return Class.forName(className);
+ } catch (ClassNotFoundException e) {
+ // Theoretically impossible.
+ throw new IllegalStateException(
+ "Could not do class lookup for class in our stack trace?!?");
+ }
+ }
+
+ private static void validateInput(InputStream is, String location)
+ throws FileNotFoundException {
+ if (is == null) {
+ throw new FileNotFoundException(String.format("Could not find file at '%s'", location));
+ }
+ }
+
}
Code Review / appc.git / blobdiff