X-Git-Url: https://gerrit.simantics.org/r/gitweb?p=simantics%2Fplatform.git;a=blobdiff_plain;f=bundles%2Forg.simantics.charts%2Fsrc%2Forg%2Fsimantics%2Fcharts%2Finternal%2FJsonUtils.java;fp=bundles%2Forg.simantics.charts%2Fsrc%2Forg%2Fsimantics%2Fcharts%2Finternal%2FJsonUtils.java;h=31861ea274bb45a40f4df85d88acbf7142c6408c;hp=0000000000000000000000000000000000000000;hb=777f66ad0fc587dd8d313705442dd2338c65ad30;hpb=8a847992137e9da5922f12d9f70273e65d77fe8d

diff --git a/bundles/org.simantics.charts/src/org/simantics/charts/internal/JsonUtils.java b/bundles/org.simantics.charts/src/org/simantics/charts/internal/JsonUtils.java
new file mode 100644
index 000000000..31861ea27
--- /dev/null
+++ b/bundles/org.simantics.charts/src/org/simantics/charts/internal/JsonUtils.java
@@ -0,0 +1,71 @@
+package org.simantics.charts.internal;
+
+import java.io.IOException;
+import java.util.Optional;
+
+import org.simantics.db.ReadGraph;
+import org.simantics.db.RequestProcessor;
+import org.simantics.db.common.request.UniqueRead;
+import org.simantics.db.exception.DatabaseException;
+import org.simantics.db.layer0.variable.Variable;
+import org.simantics.db.layer0.variable.Variables;
+
+import com.fasterxml.jackson.core.JsonFactory;
+import com.fasterxml.jackson.core.JsonParser;
+import com.fasterxml.jackson.core.JsonToken;
+
+/**
+ * @author Tuukka Lehtonen
+ *
+ */
+public class JsonUtils {
+
+    public static Optional<Variable> tryParseJsonPropertyVariable(RequestProcessor processor, String json) throws DatabaseException {
+        return processor.syncRequest(new UniqueRead<Optional<Variable>>() {
+            @Override
+            public Optional<Variable> perform(ReadGraph graph) throws DatabaseException {
+                return tryParseJsonPropertyVariable(graph, json);
+            }
+        });
+    }
+
+    public static Optional<Variable> tryParseJsonPropertyVariable(ReadGraph graph, String json) throws DatabaseException {
+        try (JsonParser jp = new JsonFactory().createParser(json)) {
+            return JsonUtils.readPossibleVariable(graph, jp);
+        } catch (IOException e) {
+            throw new DatabaseException(e);
+        }
+    }
+
+    public static Optional<Variable> readPossibleVariable(ReadGraph graph, JsonParser jp) throws IOException, DatabaseException {
+        Optional<String> uri = readPossibleVariableUri(jp);
+        return uri.isPresent() ? Optional.ofNullable(Variables.getPossibleVariable(graph, uri.get())) : Optional.empty();
+    }
+
+    public static Optional<String> readPossibleVariableUri(JsonParser jp) throws IOException {
+        // Sanity check: verify that we got "Json Object":
+        if (jp.nextToken() != JsonToken.START_OBJECT)
+            throw new IOException("Expected data to start with an Object");
+
+        String uri = null;
+        String type = null;
+        String defaultPropertyUri = null;
+
+        while (jp.nextToken() != JsonToken.END_OBJECT) {
+            String fieldName = jp.getCurrentName();
+            jp.nextToken();
+            if (fieldName.equals("uri")) {
+                uri = jp.getValueAsString();
+            } else if (fieldName.equals("type")) {
+                type = jp.getValueAsString();
+            } else if (fieldName.equals("defaultPropertyUri")) {
+                defaultPropertyUri = jp.getValueAsString();
+            }
+        }
+
+        return Optional.ofNullable("Variable".equals(type) ?
+                defaultPropertyUri != null ? defaultPropertyUri : uri
+                        : null);
+    }
+
+}