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Content Streams

Every PdfPage has an internal content stream — a sequence of PDF operators that describes what to draw. PDFixa writes these operators deterministically in the order you call the drawing methods.

Drawing operations​

Text​

// drawTextBox(x, y, width, height, text)
page.drawTextBox(72, 700, 450, 40, "Hello, world!");

Draws text inside a box anchored at (x, y). If the text is longer than the box width, it wraps. The height clips overflow.

Lines and shapes​

// Horizontal line from (x1, y) to (x2, y)
page.drawLine(72, 680, 523, 680);

// Rectangle outline at (x, y) with given width and height
page.drawRect(72, 500, 450, 100);

// Filled rectangle
page.fillRect(72, 500, 450, 100);

Images​

byte[] imageBytes = Files.readAllBytes(Path.of("logo.png"));
page.drawImage(72, 750, 120, 40, imageBytes);

See Images for supported formats and embedding details.

Operation order​

Operations are appended to the content stream in the order you call them. Later operations are painted on top of earlier ones. There is no z-index — order is the only layering mechanism.

page.fillRect(72, 700, 200, 50);          // background box (painted first)
page.drawTextBox(80, 710, 184, 30, "Label");  // text on top (painted second)

Determinism guarantee​

PDFixa writes the content stream in a fixed, reproducible format. Given the same sequence of draw calls, the resulting stream bytes are identical on every run. No floating-point variance, no locale-dependent formatting, no timestamps.

See Deterministic Output for the full picture.