Pipeline launch log error (#104)

* check and log error

* update function documentation from official gstreamer 1.8

* add parseLaunch and parseBinFromDescription

Author: i-n-g-o

src/org/freedesktop/gstreamer/Gst.java

@@ -59,6 +59,8 @@
 import com.sun.jna.ptr.IntByReference;
 import com.sun.jna.ptr.PointerByReference;
 import java.util.Arrays;
+import java.util.logging.Level;
+import static org.freedesktop.gstreamer.lowlevel.GstParseAPI.GSTPARSE_API;
 
 /**
  * Media library supporting arbitrary formats and filter graphs.
@@ -201,6 +203,109 @@ public static void quit() {
         quit.countDown();
     }
 
+    
+    /**
+     * Create a new pipeline based on command line syntax.
+     * 
+     * Please note that you might get a return value that is not NULL even 
+     * though the error is set. 
+     * In this case there was a recoverable parsing error and you can try 
+     * to play the pipeline.
+     * 
+     * @param pipelineDescription  the command line describing the pipeline
+     * @return a new element on success. 
+     *         If more than one toplevel element is specified by 
+     *         the pipeline_description , all elements are put into a GstPipeline, 
+     *         which than is returned. 
+     */
+    public static Pipeline parseLaunch(String pipelineDescription, List<GError> errors) {
+        Pointer[] err = { null };
+        Pipeline pipeline = GSTPARSE_API.gst_parse_launch(pipelineDescription, err);
+        if (pipeline == null) {
+            throw new GstException(new GError(new GErrorStruct(err[0])));
+        }
+        
+        // check for error
+        if (err[0] != null) { 
+            if (errors != null) {
+                errors.add(new GError(new GErrorStruct(err[0])));
+            } else {
+                logger.log(Level.WARNING, new GError(new GErrorStruct(err[0])).getMessage());
+            }
+        }
+
+        return pipeline;
+    }    
+    public static Pipeline parseLaunch(String pipelineDescription) {
+        return parseLaunch(pipelineDescription, null);
+    }
+    
+    /**
+     * Create a new element based on command line syntax. 
+     * 
+     * error will contain an error message if an erroneous pipeline is specified. 
+     * An error does not mean that the pipeline could not be constructed.
+     * 
+     * @param pipelineDescription An array of strings containing the command line describing the pipeline.
+     * @return a new element on success. 
+     */
+    public static Pipeline parseLaunch(String[] pipelineDescription, List<GError> errors) {
+        Pointer[] err = { null };
+        Pipeline pipeline = GSTPARSE_API.gst_parse_launchv(pipelineDescription, err);
+        if (pipeline == null) {
+            throw new GstException(new GError(new GErrorStruct(err[0])));
+        }
+        
+        // check for error
+        if (err[0] != null) { 
+            if (errors != null) {
+                errors.add(new GError(new GErrorStruct(err[0])));
+            } else {
+                logger.log(Level.WARNING, new GError(new GErrorStruct(err[0])).getMessage());
+            }
+        }
+
+        return pipeline;
+    }
+    public static Pipeline parseLaunch(String[] pipelineDescription) {
+        return parseLaunch(pipelineDescription, null);
+    }
+    
+    /**
+    * Creates a bin from a text bin description. 
+    * 
+    * This function allows creation of a bin based on the syntax used in the
+    * gst-launch utillity.
+    * 
+    * @param binDescription the command line describing the bin
+    * @param ghostUnlinkedPads whether to create ghost pads for the bin from any unlinked pads
+    * @return The new Bin.
+    */
+   public static Bin parseBinFromDescription(String binDescription, boolean ghostUnlinkedPads, List<GError> errors) {
+        
+        Pointer[] err = { null };
+        Bin bin = GSTPARSE_API.gst_parse_bin_from_description(binDescription, ghostUnlinkedPads, err);
+
+        if (bin == null) {       
+            throw new GstException(new GError(new GErrorStruct(err[0])));
+        }
+
+        // check for error
+        if (err[0] != null) { 
+            if (errors != null) {
+                errors.add(new GError(new GErrorStruct(err[0])));
+            } else {
+                logger.log(Level.WARNING, new GError(new GErrorStruct(err[0])).getMessage());
+            }
+        }
+        
+        return bin;
+   }
+   public static Bin parseBinFromDescription(String binDescription, boolean ghostUnlinkedPads) {
+       return parseBinFromDescription(binDescription, ghostUnlinkedPads, null);
+   }
+    
+    
     /**
      * Waits for the gstreamer system to shutdown via a call to {@link #quit}.
      * <p> For most gui programs, this is of little use.  However, it can be

src/org/freedesktop/gstreamer/Pipeline.java

@@ -23,6 +23,8 @@
 import java.util.concurrent.TimeUnit;
 
 import com.sun.jna.Pointer;
+import java.util.logging.Level;
+import java.util.logging.Logger;
 
 import org.freedesktop.gstreamer.lowlevel.GstAPI.GErrorStruct;
 
@@ -89,6 +91,8 @@ public class Pipeline extends Bin {
     public static final String GST_NAME = "pipeline";
     public static final String GTYPE_NAME = "GstPipeline";
 
+    private static Logger logger = Logger.getLogger(Pipeline.class.getName());
+        
     public Pipeline(Initializer init) { 
         super(init);
     }
@@ -117,10 +121,12 @@ private static Initializer initializer(String name) {
 	}
 
     /**
-     * Creates a pipeline from a text pipeline description.
+     * Create a new pipeline based on command line syntax.
      * 
-     * This function allows creation of a pipeline based on the syntax used in the
-     * gst-launch utillity.
+     * Please note that you might get a return value that is not NULL even 
+     * though the error is set. 
+     * In this case there was a recoverable parsing error and you can try 
+     * to play the pipeline.
      * 
      * @param pipelineDecription  the command line describing the pipeline
      * @return The new Pipeline.
@@ -131,15 +137,21 @@ public static Pipeline launch(String pipelineDecription) {
         if (pipeline == null) {
             throw new GstException(new GError(new GErrorStruct(err[0])));
         }
+        
+        // check for error
+        if (err[0] != null) { 
+            logger.log(Level.WARNING, new GError(new GErrorStruct(err[0])).getMessage());
+        }
+
         pipeline.initBus();
         return pipeline;
     }
 
     /**
-     * Creates a pipeline from a text pipeline description.
+     * Create a new element based on command line syntax.
      * 
-     * This function allows creation of a pipeline based on the syntax used in the
-     * gst-launch utillity.
+     * error will contain an error message if an erroneous pipeline is specified. 
+     * An error does not mean that the pipeline could not be constructed.
      * 
      * @param pipelineDecription An array of strings containing the command line describing the pipeline.
      * @return The new Pipeline.
@@ -150,6 +162,13 @@ public static Pipeline launch(String... pipelineDecription) {
         if (pipeline == null) {
             throw new GstException(new GError(new GErrorStruct(err[0])));
         }
+        
+        // check for error
+        if (err[0] != null) {
+            // log error!            
+            logger.log(Level.WARNING, new GError(new GErrorStruct(err[0])).getMessage());
+        }
+
         pipeline.initBus();
         return pipeline;
     }