PDFlib

高度なPDFアプリケーションの開発を支援する定番プログラムライブラリー Supported by インフォテック株式会社

PDFlib サンプル集(クックブック)

本サンプルプログラムは、PDF 文書生成ライブラリーの実装である PDFlib の基本的な機能を実際のプログラムで紹介したものです。

本サイトでダウンロードした PDFlib は、一部機能の制限を除き、評価版として無償でお使いいただけます。

関数のスコープ

最新の PDFlib 9では関数スコープを再設計し、多くの制限がなくなりました。

このサンプルは PDFlib 8 以前の古い関数スコープに関するものです。

PDFlib API スコープの概念についてのサンプルプログラムです。テキスト、グラフィック、イメージを出力したページを作成します。スコープがどのように関連付けられ、関数の呼び出しによってどのようにスコープが始まり、そして終了するのかを見ることができます。どのような状況で使用することができたり、許されなかったりを確認できます。現在のスコープを問い合わせるために、get_parameter("scope", 0) を使用します。


/* $Id: function_scopes.java,v 1.3 2008/01/14 11:41:15 katja Exp $
 * Function scopes:
 * Explain the concept of scopes of the PDFlib API
 * 
 * Create a few pages and output some text, graphics and images. Show how scopes
 * are related and how function calls start or terminate scopes. Show which 
 * calls can be used in the respective situation and which calls are not
 * allowed. Use get_parameter("scope", 0) to query the current scope.
 *
 * Required software: PDFlib Lite/PDFlib/PDFlib+PDI/PPS 7
 * Required data: image file
 */
import com.pdflib.pdflib;
import com.pdflib.PDFlibException;

public class function_scopes
{
    public static void main (String argv[])
    {
    /* This is where the data files are. Adjust as necessary. */
    String searchpath = "../input";
    String outfile = "function_scopes.pdf";
    String title = "Function Scopes";

    pdflib p = null;
    String imagefile = "nesrin.jpg";
    String scope;
    int font, image;

    try {
        /* -------------------------------------------------------------------
         * Create a PDFlib object.
         * 
         * This call starts scope "object".
         * Only begin_document(), get_buffer(), and encoding_set_char() can be
         * called in this scope.
         * -------------------------------------------------------------------
         */
        p = new pdflib();
        
        p.set_parameter("SearchPath", searchpath);

        /* This means we must check return values of load_font() etc. */
        p.set_parameter("errorpolicy", "return");
        
        
        /* --------------------------------------------------------------------
         * Start the document.
         * 
         * This call starts scope "document".
         * The following functions plus some others are allowed in this scope:
         * begin_page_ext(), resume_page(), load_image(), begin_template_ext(),
         * open_pdi_document(), open_pdi_page().
         * --------------------------------------------------------------------
         */
        if (p.begin_document(outfile, "") == -1)
            throw new Exception("Error: " + p.get_errmsg());

        p.set_info("Creator", "PDFlib Cookbook");
        p.set_info("Title", title + " $Revision: 1.3 $");

        /* We load the image before the first page, and use it on all pages.
         * Loading an image is allowed in scope "document".
         */
        image = p.load_image("auto", imagefile, "");

        if (image == -1)
            throw new Exception("Error: " + p.get_errmsg());
        

        /* -------------------------------------------------------------------
         * Start the first page.
         * 
         * This call starts scope "page".
         * Many functions for creating page content are allowed in this scope.
         * -------------------------------------------------------------------
         */
        p.begin_page_ext(595, 842, "");
        
        /* Load the font.
         *  
         * Loading a font is allowed in any scope except "object". Therefore,
         * it can also be done in scope "document" before starting the page.
         * 
         * For PDFlib Lite: change "unicode" to "winansi".
         */
        font = p.load_font("Helvetica", "unicode", "");

        if (font == -1)
            throw new Exception("Error: " + p.get_errmsg());
        
        /* Set the font, output an image, and output a text line.
         * 
         * These three function calls are allowed in scope "page" but cannot be
         * used in scope "document". This means that the page must have been
         * started first as accomplished above.
         */
        p.setfont(font, 14);
        
        p.fit_image(image,  200.0,  200.0, "scale=0.25");
        
        /* Output the scope.
         * 
         * Use get_parameter() with the key "scope" to query the current scope.
         */
        scope = p.get_parameter("scope", 0);
        p.fit_textline("The current scope can be retrieved with " +
            "get_parameter(\"scope\", 0);", 20, 700, "");
        
        
        /* --------------------------------------------------------------------
         * Complete the first page.
         * 
         * This call terminates scope "page". After this call the current scope
         * will be "document" again. 
         * --------------------------------------------------------------------
         */
        p.end_page_ext("");
        

        /* -----------------------------
         * Start the second page.
         * 
         * This call starts scope "page"
         * -----------------------------
         */
        p.begin_page_ext(595, 842, "");

        /* Set the current fill color. 
         * 
         * This call is allowed in scope "page" but cannot be used in scope
         * "document".
         */
        p.setcolor("fill", "rgb", 1.0, 0.0, 0.0, 0.0);
        
        
        /* -------------------------------------------------------------------
         * Add a rectangle to the current path.
         * 
         * This call starts scope "path".
         * Only other functions for constructing paths can be called in "path"
         * scope, e.g. lineto() or closepath(). None of the graphics state
         * functions or saving/restoring the graphics state, or setting the
         * current color must be used in "path" scope.
         * -------------------------------------------------------------------
         */
        p.rect(200, 200, 250, 150);
        
        
        /* --------------------------------------------------------------------
         * Fill the interior of the path with the current fill color.
         * 
         * This call terminates scope "path". After this call the current scope
         * will be "page" again. 
         * --------------------------------------------------------------------
         */
        p.fill();
        
        /* Set the current line width. This call is allowed in scope "page". */
        p.setlinewidth(10);
        
        /* Set the current point for graphics output.
         * 
         * This function starts the scope "path".
         */
        p.moveto(100, 500);
        
        /* Add a line to the current path */
        p.lineto(300, 700);
        
        
        /* ---------------------------------------------------------------------
         * Stroke the path with the current line width and current stroke color,
         * and clear it.
         * 
         * This function terminates scope "path". After this call the current
         * scope will be "page" again.
         * --------------------------------------------------------------------- 
         */
        p.stroke();
        

        /* --------------------------------------------------------------------
         * Complete the first page.
         * 
         * This call terminates scope "page". After this call the current scope
         * will be "document" again. 
         * --------------------------------------------------------------------
         */
        p.end_page_ext("");

        /* Close the image. This call could have also be used in scope "page"
         * before ending the page.
         */
        p.close_image(image);
        
        
        /* ----------------------------------------------------------------
         * This call terminates scope "document". The current scope will be
         * "object" again
         * ----------------------------------------------------------------
         */
        p.end_document("");

        } catch (PDFlibException e) {
            System.err.print("PDFlib exception occurred:\n");
            System.err.print("[" + e.get_errnum() + "] " + e.get_apiname() +
                ": " + e.get_errmsg() + "\n");
        } catch (Exception e) {
            System.err.println(e.getMessage());
        } finally {
            if (p != null) {
                p.delete();
            }
        }
    }
}
(Apr 3, 2007 - Feb 20, 2014)