Improve integration capabilities.

[lgpl/argeo-commons.git] / org.argeo.cms / src / org / argeo / cms / integration / CmsExceptionsChain.java

diff --git a/org.argeo.cms/src/org/argeo/cms/integration/CmsExceptionsChain.java b/org.argeo.cms/src/org/argeo/cms/integration/CmsExceptionsChain.java
new file mode 100644 (file)
index 0000000..d7a51b7
--- /dev/null
+++ b/org.argeo.cms/src/org/argeo/cms/integration/CmsExceptionsChain.java
@@ -0,0 +1,74 @@
+package org.argeo.cms.integration;
+
+import java.io.IOException;
+import java.io.Writer;
+
+import javax.servlet.http.HttpServletResponse;
+
+import org.argeo.util.ExceptionsChain;
+
+import com.fasterxml.jackson.core.JsonGenerator;
+import com.fasterxml.jackson.core.JsonProcessingException;
+import com.fasterxml.jackson.databind.ObjectMapper;
+
+/** Serialisable wrapper of a {@link Throwable}. */
+public class CmsExceptionsChain extends ExceptionsChain {
+       public CmsExceptionsChain() {
+               super();
+       }
+
+       public CmsExceptionsChain(Throwable exception) {
+               super(exception);
+       }
+
+       public String toJsonString(ObjectMapper objectMapper) {
+               try {
+                       return objectMapper.writeValueAsString(this);
+               } catch (JsonProcessingException e) {
+                       throw new IllegalStateException("Cannot write system exceptions " + toString(), e);
+               }
+       }
+
+       public void writeAsJson(ObjectMapper objectMapper, Writer writer) {
+               try {
+                       JsonGenerator jg = objectMapper.getFactory().createGenerator(writer);
+                       jg.writeObject(this);
+               } catch (IOException e) {
+                       throw new IllegalStateException("Cannot write system exceptions " + toString(), e);
+               }
+       }
+
+       public void writeAsJson(ObjectMapper objectMapper, HttpServletResponse resp) {
+               try {
+                       resp.setContentType("application/json");
+                       resp.setStatus(500);
+                       writeAsJson(objectMapper, resp.getWriter());
+               } catch (IOException e) {
+                       throw new IllegalStateException("Cannot write system exceptions " + toString(), e);
+               }
+       }
+
+       public static void main(String[] args) throws Exception {
+               try {
+                       try {
+                               try {
+                                       testDeeper();
+                               } catch (Exception e) {
+                                       throw new Exception("Less deep exception", e);
+                               }
+                       } catch (Exception e) {
+                               throw new RuntimeException("Top exception", e);
+                       }
+               } catch (Exception e) {
+                       CmsExceptionsChain vjeSystemErrors = new CmsExceptionsChain(e);
+                       ObjectMapper objectMapper = new ObjectMapper();
+                       System.out.println(objectMapper.writerWithDefaultPrettyPrinter().writeValueAsString(vjeSystemErrors));
+                       e.printStackTrace();
+               }
+       }
+
+       static void testDeeper() throws Exception {
+               throw new IllegalStateException("Deep exception");
+       }
+
+}