Last active
December 6, 2022 19:35
-
-
Save spoptchev/e0821c4bf39032eb1f5f208f2f8fd8d8 to your computer and use it in GitHub Desktop.
How to improve third-party libraries with Kotlin extensions
This file contains bidirectional Unicode text that may be interpreted or compiled differently than what appears below. To review, open the file in an editor that reveals hidden Unicode characters.
Learn more about bidirectional Unicode characters
| package tech.zone2.mime | |
| import org.apache.james.mime4j.dom.Message | |
| import org.apache.james.mime4j.dom.Multipart | |
| import org.apache.james.mime4j.message.BodyPartBuilder | |
| import org.apache.james.mime4j.message.MultipartBuilder | |
| import tech.zone2.mime.html | |
| import tech.zone2.mime.text | |
| fun main() { | |
| val textPart = BodyPartBuilder.create() | |
| .setBody("plain text content", "plain", Charsets.UTF_8) | |
| val htmlPart = BodyPartBuilder.create() | |
| .setBody("<html><body>content</body></html>", "html", Charsets.UTF_8) | |
| val multipart: Multipart = MultipartBuilder.create("alternative") | |
| .addBodyPart(textPart) | |
| .addBodyPart(htmlPart) | |
| .build() | |
| val message = Message.Builder.of() | |
| .setBody(multipart) | |
| .build() | |
| println(message.text) // -> plain text content | |
| println(message.html) // -> <html><body>content</body></html> | |
| } |
This file contains bidirectional Unicode text that may be interpreted or compiled differently than what appears below. To review, open the file in an editor that reveals hidden Unicode characters.
Learn more about bidirectional Unicode characters
| package tech.zone2.mime | |
| import org.apache.james.mime4j.Charsets | |
| import org.apache.james.mime4j.dom.Entity | |
| import org.apache.james.mime4j.dom.Message | |
| import org.apache.james.mime4j.dom.Multipart | |
| import org.apache.james.mime4j.dom.TextBody | |
| import org.apache.james.mime4j.dom.field.FieldName | |
| import java.io.ByteArrayOutputStream | |
| import java.nio.charset.Charset | |
| import java.nio.charset.IllegalCharsetNameException | |
| import java.nio.charset.UnsupportedCharsetException | |
| private const val textHtml = "text/html" | |
| private const val textPlain = "text/plain" | |
| val Message.html: String? | |
| get() { | |
| val textBody = findTextBody(setOf(textHtml)) ?: return null | |
| return textBody.content | |
| } | |
| val Message.text: String? | |
| get() { | |
| val textBody = findTextBody(setOf(textPlain, null)) ?: return null | |
| return textBody.content | |
| } | |
| private val Entity.isNotAttachment | |
| get() = dispositionType == null | |
| private val Entity.isInlinedWithoutCid | |
| get() = dispositionType == "inline" && header.getField(FieldName.CONTENT_ID) == null | |
| private fun Entity.findTextBody(validMimeTypes: Set<String?>): TextBody? { | |
| if (body is TextBody && mimeType in validMimeTypes && (isNotAttachment || isInlinedWithoutCid)) { | |
| return body as TextBody | |
| } | |
| if (!isMultipart) { | |
| return null | |
| } | |
| return (body as Multipart).bodyParts | |
| .firstNotNullOfOrNull { it.findTextBody(validMimeTypes) } | |
| } | |
| private val TextBody.contentCharset | |
| get() = try { | |
| Charset.forName(mimeCharset) | |
| } catch (e: IllegalCharsetNameException) { | |
| Charsets.DEFAULT_CHARSET | |
| } catch (e: IllegalArgumentException) { | |
| Charsets.DEFAULT_CHARSET | |
| } catch (e: UnsupportedCharsetException) { | |
| Charsets.DEFAULT_CHARSET | |
| } | |
| private val TextBody.content: String | |
| get() { | |
| val byteArrayOutputStream = ByteArrayOutputStream() | |
| writeTo(byteArrayOutputStream) | |
| return String(byteArrayOutputStream.toByteArray(), contentCharset) | |
| } | |
Sign up for free
to join this conversation on GitHub.
Already have an account?
Sign in to comment