This project is based on wkhtmltopdf, which converts HTML documents to PDF. Access to wkhtmltopdf is performed via JNA, exposed through a Java-friendly layer.
Gradle:
compile 'io.woo:htmltopdf:1.0.5'
Maven:
<dependency>
<groupId>io.woo</groupId>
<artifactId>htmltopdf</artifactId>
<version>1.0.5</version>
<scope>compile</scope>
</dependency>
The following examples should be sufficient to get you started, however there
are many more options discoverable by looking into the methods of HtmlToPdf
and HtmlToPdfObject
.
boolean success = HtmlToPdf.create()
.object(HtmlToPdfObject.forHtml("<p><em>Apples</em>, not oranges</p>"))
.convert("/path/to/file.pdf");
boolean success = HtmlToPdf.create()
.object(HtmlToPdfObject.forUrl("https://github.com/wooio/htmltopdf-java"))
.convert("/path/to/file.pdf");
boolean success = HtmlToPdf.create()
.object(HtmlToPdfObject.forUrl("https://github.com/wooio/htmltopdf-java"))
.object(HtmlToPdfObject.forHtml("<p>This is the second object...</p>"))
// ...
.convert("/path/to/file.pdf");
Converting to an InputStream would be useful if you intend on returning the resulting PDF document as an HTTP response or adding it as an email attachment
HtmlToPdf htmlToPdf = HtmlToPdf.create()
// ...
.object(HtmlToPdfObject.forUrl("https://github.com/wooio/htmltopdf-java"));
try (InputStream in = htmlToPdf.convert()) {
// "in" has PDF bytes loaded
} catch (HtmlToPdfException e) {
// HtmlToPdfException is a RuntimeException, thus you are not required to
// catch it in this scope. It is thrown when the conversion fails
// for any reason.
}
While the library is thread-safe, it unfortunately cannot perform conversions concurrently. Because wkhtmltopdf uses Qt behind the scenes to render webpages, there is a single thread which performs such rendering across a single process. Therefore, at this point, it is only possible to perform one conversion at the same time per process.
If you get the following exception:
java.lang.UnsatisfiedLinkError: Unable to load library '/tmp/io.woo.htmltopdf/wkhtmltox/0.12.4/libwkhtmltox.so': Native library (tmp/io.woo.htmltopdf/wkhtmltox/0.12.4/libwkhtmltox.so) not found in resource path
Then that likely means that one of the native dependencies of wkhtmltopdf is not met. It might be worth checking that the following packages are installed:
- libc6 (or glibc)
- libx11
- libxext
- libxrender
- libstdc++
- libssl1.0
- freetype
- fontconfig