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>From: Tom Whittaker <address@hidden> >Organization: SSEC >Keywords: 200402111527.i1BFRQp1019091 Tom- >When I try to get this file: > >http://cimss.ssec.wisc.edu/model/daily/cras00.v5d > >as a URL of type Vis5D, I get the follow exception. Well, if it doesn't work, don't do that. ;-) >If I download the file >and read it locally, it reads and displays just fine. Do this instead. ;-) The problem is that the V5DStruct uses a RandomAccessFile which won't work on a remote file. It might be possible to use the HTTPRandomAccessFile like netCDF does, but that would involve a change to the visad.data.Vis5DForm package. >Contained exception:null >java.lang.NullPointerException > at ucar.unidata.data.grid.GridUtil.isSequence(GridUtil.java:270) > at ucar.unidata.data.grid.GridUtil.isTimeSequence(GridUtil.java:286) > at >ucar.unidata.data.grid.Vis5DDataSource.doMakeDataChoices(Vis5DDataSource.java: > 141) > at ucar.unidata.data.DataSourceImpl.getDataChoices(DataSourceImpl.java: > 781) > at ucar.unidata.data.DataManager.createDataSource(DataManager.java:799) > at >ucar.unidata.idv.IntegratedDataViewer.createDataSource(IntegratedDataViewer.ja > va:1381) > at >ucar.unidata.idv.IntegratedDataViewer.makeDataSource(IntegratedDataViewer.java > :1327) > at >ucar.unidata.idv.IntegratedDataViewer.handleAction(IntegratedDataViewer.java:1 > 163) > at >ucar.unidata.idv.IntegratedDataViewer.handleAction(IntegratedDataViewer.java:1 > 128) > at ucar.unidata.idv.chooser.UrlChooser.loadURLInner(UrlChooser.java:150 > ) > at ucar.unidata.idv.chooser.UrlChooser.loadURL(UrlChooser.java:126) > at ucar.unidata.idv.chooser.UrlChooser.access$000(UrlChooser.java:71) > at ucar.unidata.idv.chooser.UrlChooser$1.run(UrlChooser.java:169) > at ucar.unidata.util.Misc$1.run(Misc.java:1281) > >Exception thrown at: >Error creating data source:file.vis5d >with:http://cimss.ssec.wisc.edu/model/daily/cras00.v5d > >ucar.unidata.data.BadDataException: Error creating data source:file.vis5d >with:http://cimss.ssec.wisc.edu/model/daily/cras00.v5d >java.lang.NullPointerException > at ucar.unidata.data.DataManager.createDataSource(DataManager.java:829) > at >ucar.unidata.idv.IntegratedDataViewer.createDataSource(IntegratedDataViewer.ja > va:1381) > at >ucar.unidata.idv.IntegratedDataViewer.makeDataSource(IntegratedDataViewer.java > :1327) > at >ucar.unidata.idv.IntegratedDataViewer.handleAction(IntegratedDataViewer.java:1 > 163) > at >ucar.unidata.idv.IntegratedDataViewer.handleAction(IntegratedDataViewer.java:1 > 128) > at ucar.unidata.idv.chooser.UrlChooser.loadURLInner(UrlChooser.java:150 > ) > at ucar.unidata.idv.chooser.UrlChooser.loadURL(UrlChooser.java:126) > at ucar.unidata.idv.chooser.UrlChooser.access$000(UrlChooser.java:71) > at ucar.unidata.idv.chooser.UrlChooser$1.run(UrlChooser.java:169) > at ucar.unidata.util.Misc$1.run(Misc.java:1281) Would you like a better error message? Don Murray