使用aspose.words为Word插入水印

1. 前言

继几个月前的word模板打印美化之后，最近又接到的一个需求是需要给由word转换为的pdf打上水印。经过几个小时的折腾发现直接在pdf打上的水印将下面的字体覆盖效果过于明显，试图插入背景图片又发现会被pdf自身的背景色给遮挡。无奈只能从源头的word入手。

2. 详解

以下就是核心代码了

/**
 * Inserts a watermark into a document.  you need saved the doc by yourself.
 *
 * @param doc The input document file.
 * @param watermarkText Text of the watermark.
 */
public static void insertWatermarkText(Document doc, String watermarkText) {
    // 居中
    insertWatermarkText(doc, watermarkText, new Function<Shape, Object>() {
        @Override
        public Object apply(Shape watermark) {
            // Place the watermark in the page center.
            watermark.setRelativeHorizontalPosition(RelativeHorizontalPosition.PAGE);
            watermark.setRelativeVerticalPosition(RelativeVerticalPosition.PAGE);
            watermark.setWrapType(WrapType.NONE); // TOP_BOTTOM : 将所设置位置的内容往上下顶出去
            watermark.setVerticalAlignment(VerticalAlignment.CENTER);
            watermark.setHorizontalAlignment(HorizontalAlignment.CENTER);

            return null;
        }
    });
    // 顶部
    insertWatermarkText(doc, watermarkText, new Function<Shape, Object>() {
        @Override
        public Object apply(Shape watermark) {
            watermark.setRelativeHorizontalPosition(RelativeHorizontalPosition.MARGIN);
            watermark.setRelativeVerticalPosition(RelativeVerticalPosition.MARGIN);
            watermark.setWrapType(WrapType.NONE);
            //  我们需要自定义距离顶部的高度      
            // watermark.setVerticalAlignment(VerticalAlignment.TOP);
            watermark.setHorizontalAlignment(HorizontalAlignment.CENTER);
            // 设置距离顶部的高度
            watermark.setTop(160);

            return null;    
        }
    });
    // 底部
    insertWatermarkText(doc, watermarkText, new Function<Shape, Object>() {
        @Override
        public Object apply(Shape watermark) {
            watermark.setRelativeHorizontalPosition(RelativeHorizontalPosition.MARGIN);
            watermark.setRelativeVerticalPosition(RelativeVerticalPosition.MARGIN);
            watermark.setWrapType(WrapType.NONE);
            // 我们需要自定义距离顶部的高度       
            // watermark.setVerticalAlignment(VerticalAlignment.BOTTOM);
            watermark.setHorizontalAlignment(HorizontalAlignment.CENTER);
            // 设置距离顶部的高度
            watermark.setTop(480);

            return null;
        }
    });
}

private static void insertWatermarkText(Document doc, String watermarkText,
        Function<Shape, Object> watermaskPositionConfigFunc)  {
    // Create a watermark shape. This will be a WordArt shape.
    // You are free to try other shape types as watermarks.
    Shape watermark = new Shape(doc, ShapeType.TEXT_PLAIN_TEXT);
    // Set up the text of the watermark.
    watermark.getTextPath().setText(watermarkText);


    // Set up the text of the watermark.
    // 这里设置为宋体可以保证在转换为PDF时中文不是乱码.
    watermark.getTextPath().setFontFamily("宋体");//Arial; 
    try {
        // 水印大小
        watermark.setWidth(200);
        watermark.setHeight(50);
    } catch (Exception e) {
        throw new RuntimeException(e);
    }
    // Text will be directed from the bottom-left to the top-right corner.
    // 左下到右上
    watermark.setRotation(-40);

    // Remove the following two lines if you need a solid black text.
    final String colorStr = "E0E0E0";
    watermark.getFill().setColor(new java.awt.Color(Integer.parseInt(colorStr, 16))); // Try Color.lightGray to get more Word-style watermark
    watermark.setStrokeColor(new java.awt.Color(Integer.parseInt(colorStr, 16))); // Try Color.lightGray to get more Word-style watermark                   

    // Place the watermark in the special location of page .
    watermaskPositionConfigFunc.apply(watermark);

    // Create a new paragraph and append the watermark to this paragraph.
    Paragraph watermarkPara = new Paragraph(doc);
    watermarkPara.appendChild(watermark);

    // Insert the watermark into all headers of each document section.
    for (Section sect : doc.getSections()) {
        // There could be up to three different headers in each section, since we want
        // the watermark to appear on all pages, insert into all headers.
        insertWatermarkIntoHeader(watermarkPara, sect, HeaderFooterType.HEADER_PRIMARY);
        // 以下注释掉不影响效果, 未作深入研究, 时间有限.
        //          insertWatermarkIntoHeader(watermarkPara, sect, HeaderFooterType.HEADER_FIRST);
        //          insertWatermarkIntoHeader(watermarkPara, sect, HeaderFooterType.HEADER_EVEN);
    }
    // 参考下API : https://apireference.aspose.com/java/words/com.aspose.words/ShapeBase
    //watermark.setZOrder(-100);
}

private static void insertWatermarkIntoHeader(Paragraph watermarkPara, Section sect,
        int headerType) {
    HeaderFooter header = sect.getHeadersFooters().getByHeaderFooterType(headerType);

    if (header == null) {
        // There is no header of the specified type in the current section, create it.
        header = new HeaderFooter(sect.getDocument(), headerType);
        sect.getHeadersFooters().add(header);
    }

    // Insert a clone of the watermark into the header.
    try {
        header.appendChild(watermarkPara.deepClone(true));
    } catch (Exception e) {
        throw new RuntimeException(e);
    }
}

4. 效果

5. Links

1. set-watermark-in-word-file-using-aspose-word