Github user aledsage commented on a diff in the pull request:
https://github.com/apache/brooklyn-server/pull/982#discussion_r214610344
--- Diff:
utils/common/src/main/java/org/apache/brooklyn/util/text/StringEscapes.java ---
@@ -315,12 +320,121 @@ else if (c=='\"') {
throw new IllegalArgumentException("String '"+s+"' is not a
valid Java string (unterminated string)");
}
+ /** @deprecated since 1.0.0, use {@link
#unwrapJsonishListStringIfPossible(String)} (old semantics)
+ * or {@link #unwrapJsonishListStringIfPossible(String)}
(improved) */
+ public static List<String> unwrapJsonishListIfPossible(String
input) {
+ return unwrapJsonishListStringIfPossible(input);
+ }
+
+ /** converts a comma separated list in a single string to a list
of json primitives or maps,
+ * falling back to returning the input.
+ * <p>
+ * specifically:
+ * <li> 1) if of form <code>[ X ]</code> (in brackets after trim),
parse as YAML;
+ * if parse succeeds return the result, or if parse fails,
return {@link Maybe#absent()}.
+ * <ll> 2) if not of form <code>[ X ]</code>, wrap in brackets and
parse as YAML,
+ * and if that succeeds and is a list, return the result.
+ * <li> 3) otherwise, expect comma-separated tokens which after
trimming are of the form "A" or B,
+ * where "A" is a valid Java string or C is any string not
starting with '
+ * and not containing " or ,. return the list of those
tokens, where A and B
+ * are their string value, and C as a primitive if it is a
number or boolean or null,
+ * or else a string, including the empty string if empty.
+ * <li> 4) if such tokens are not found, return {@link
Maybe#absent()}.
+ * <p>
+ * @see #unwrapOptionallyQuotedJavaStringList(String)
+ **/
+ public static Maybe<List<Object>> tryUnwrapJsonishList(String
input) {
+ if (input==null) return Maybe.absent("null input cannot unwrap
to a list");
+ String inputT = input.trim();
+
+ String inputYaml = null;
+ if (!inputT.startsWith("[") && !inputT.endsWith("]")) {
+ inputYaml = "[" + inputT + "]";
+ }
+ if (inputT.startsWith("[") && inputT.endsWith("]")) {
+ inputYaml = inputT;
+ }
+ if (inputYaml!=null) {
+ try {
+ Object r = Iterables.getOnlyElement(
Yamls.parseAll(inputYaml) );
+ if (r instanceof List) {
+ @SuppressWarnings("unchecked")
+ List<Object> result = (List<Object>)r;
+ return Maybe.of(result);
+ }
+ } catch (Exception e) {}
--- End diff --
Strong preference to never have empty catch blocks. I'd do:
```
catch(Exception e) {
Exceptions.propagateIfFatal(e);
// Logic below decides whether to return absent or to keep trying
}
```
---
