docx4j设置ppr段前及断后空白距离

使用docx4j可以通过以下步骤设置ppr段前及断后空白距离：

1. 获取段落属性（PPR）对象

PPr ppr = para.getParagraph().getPPr();
if (ppr == null) {
    ppr = Context.getWmlObjectFactory().createPPr();
    para.getParagraph().setPPr(ppr);
}

2. 创建段前和断后的间距对象（JAXBElement对象）

// 段前间距
JAXBElement<BigInteger> spacingBefore = createSpacingObject(BigInteger.valueOf(200));

// 断后间距
JAXBElement<BigInteger> spacingAfter = createSpacingObject(BigInteger.valueOf(200));

3. 将间距对象添加到ppr对象中

ppr.setSpacingBefore(spacingBefore);
ppr.setSpacingAfter(spacingAfter);

完整代码示例：

private static void setParagraphSpacing(WordprocessingMLPackage wordMLPackage, P para) {
    // 获取段落属性对象
    PPr ppr = para.getParagraph().getPPr();
    if (ppr == null) {
        ppr = Context.getWmlObjectFactory().createPPr();
        para.getParagraph().setPPr(ppr);
    }

    // 创建段前和段后间距对象
    JAXBElement<BigInteger> spacingBefore = createSpacingObject(BigInteger.valueOf(200));
    JAXBElement<BigInteger> spacingAfter = createSpacingObject(BigInteger.valueOf(200));

    // 设置段前和段后间距
    ppr.setSpacingBefore(spacingBefore);
    ppr.setSpacingAfter(spacingAfter);
}

private static JAXBElement<BigInteger> createSpacingObject(BigInteger value) {
    CTSpacing spacing = Context.getWmlObjectFactory().createCTSpacing();
    spacing.setVal(value);
    spacing.setLine(BigInteger.valueOf(240)); // 设置行距

    return Context.getWmlObjectFactory().createPPrBaseSpacingBefore(spacing);
}