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package com.launchdarkly.testhelpers;
import com.google.gson.Gson;
import com.google.gson.JsonElement;
/**
* A simple wrapper for a string that can be parsed as JSON for tests.
*
* This class provides strong typing so that it is clear when test matchers apply to JSON
* values versus strings, and hides the implementation details of parsing and serialization
* which are not relevant to the test logic.
*
* @see JsonAssertions
* @since 1.1.0
*/
public final class JsonTestValue {
private static final Gson gson = new Gson();
final String raw;
final JsonElement parsed;
private JsonTestValue(String raw, JsonElement parsed) {
this.raw = raw;
this.parsed = parsed;
}
/**
* Creates a {@code JsonTestValue} from a string that should contain JSON.
*
* This method fails immediately for any string that is not well-formed JSON. However, if
* it is a null reference, it returns an "undefined" instance that will return {@code false}
* from {@link #isDefined()}.
*
* @param raw the input string
* @return a {@code JsonTestValue}
* @throws AssertionError for malformed JSON
*/
public static JsonTestValue jsonOf(String raw) {
if (raw == null) {
return new JsonTestValue(null, null);
}
try {
return new JsonTestValue(raw, gson.fromJson(raw, JsonElement.class));
} catch (Exception e) {
throw new AssertionError("not valid JSON (" + e + "): " + raw);
}
}
static JsonTestValue ofParsed(JsonElement json) {
return new JsonTestValue(json == null ? null : gson.toJson(json), json);
}
/**
* Creates a {@code JsonTestValue} by serializing an arbitrary value to JSON. For
* instance, {@code jsonFromValue(true)} is equivalent to {@code jsonOf("true")}.
*
* @param value an arbitrary value
* @return a {@code JsonTestValue}
*/
public static JsonTestValue jsonFromValue(Object value) {
return ofParsed(gson.toJsonTree(value));
}
@Override
public String toString() {
return raw == null ? "" : raw;
}
/**
* Returns true if there is a value (that is, the original string was not a null reference).
*
* @return true if defined
*/
public boolean isDefined() {
return raw != null;
}
}