Added overloads that catch exceptions and return null on error

e-invoice-domain/src/main/kotlin/net/codinux/invoicing/reader/EInvoiceReader.kt

@@ -2,6 +2,7 @@ package net.codinux.invoicing.reader
 
 import net.codinux.invoicing.mapper.MustangMapper
 import net.codinux.invoicing.model.Invoice
+import net.codinux.log.logger
 import org.mustangproject.ZUGFeRD.ZUGFeRDInvoiceImporter
 import java.io.File
 import java.io.InputStream
@@ -16,11 +17,19 @@ open class EInvoiceReader(
         )
     }
 
+    private val log by logger()
+
+
+    open fun extractFromXmlOrNull(xmlFile: File) = orNull { extractFromXml(xmlFile) }
 
     open fun extractFromXml(xmlFile: File) = xmlFile.inputStream().use { extractFromXml(it) }
 
+    open fun extractFromXmlOrNull(stream: InputStream) = orNull { extractFromXml(stream) }
+
     open fun extractFromXml(stream: InputStream) = extractFromXml(stream.reader().readText())
 
+    open fun extractFromXmlOrNull(xml: String) = orNull { extractFromXml(xml) }
+
     open fun extractFromXml(xml: String): Invoice {
         val importer = ZUGFeRDInvoiceImporter() // XRechnungImporter only reads properties but not to a Invoice object
         importer.fromXML(xml)
@@ -28,16 +37,26 @@ open class EInvoiceReader(
         return extractInvoice(importer)
     }
 
+
+    open fun extractFromPdfOrNull(pdfFile: File) = orNull { extractFromPdf(pdfFile) }
+
     open fun extractFromPdf(pdfFile: File) = pdfFile.inputStream().use { extractFromPdf(it) }
 
+    open fun extractFromPdfOrNull(stream: InputStream) = orNull { extractFromPdf(stream) }
+
     open fun extractFromPdf(stream: InputStream): Invoice {
         val importer = ZUGFeRDInvoiceImporter(stream)
 
         return extractInvoice(importer)
     }
 
+
+    open fun extractXmlFromPdfOrNull(pdfFile: File) = orNull { extractXmlFromPdf(pdfFile) }
+
     open fun extractXmlFromPdf(pdfFile: File) = pdfFile.inputStream().use { extractXmlFromPdf(it) }
 
+    open fun extractXmlFromPdfOrNull(stream: InputStream) = orNull { extractXmlFromPdf(stream) }
+
     open fun extractXmlFromPdf(stream: InputStream): String {
         val importer = ZUGFeRDInvoiceImporter(stream)
 
@@ -58,4 +77,13 @@ open class EInvoiceReader(
         return mapper.mapToInvoice(invoice)
     }
 
+
+    protected open fun <T> orNull(action: () -> T): T? =
+        try {
+            action()
+        } catch (e: Throwable) {
+            log.debug(e) { "Action caused an exception, but orNull() was called" }
+            null
+        }
+
 }