一、导致不兼容的原因

POI生成的加粗的节点<b val="true"></b>,在较低版本的wps中无法正确识别展示，可以正确识别展示的节点<b/>

二、代码

创建富文本时用WPSXSSFRichTextString替代XSSFRichTextString

package com.richtext;

import org.apache.poi.ss.usermodel.Font;
import org.apache.poi.xssf.usermodel.XSSFFont;
import org.apache.poi.xssf.usermodel.XSSFRichTextString;
import org.openxmlformats.schemas.spreadsheetml.x2006.main.*;

import java.lang.invoke.MethodHandle;
import java.lang.invoke.MethodHandles;
import java.lang.reflect.Field;
import java.lang.reflect.Method;
import java.util.TreeMap;

/**
 * <p>用于解决POI导出的Excel中富文本加粗不生效的问题，</p>
 * <p>此问题是由于较低版本的WPS不能正常识别 &lt;b val="true"/&gt;</p>
 */
public class WPSXSSFRichTextString extends XSSFRichTextString {
    public WPSXSSFRichTextString() {
        super();
    }

    public WPSXSSFRichTextString(String str) {
        super(str);
    }

    public WPSXSSFRichTextString(CTRst st) {
        super(st);
    }

    static MethodHandles.Lookup lookup = MethodHandles.lookup();
    private static Field stFeild;
    private static MethodHandle getFormatMapMethodHandle;
    // private static Method getFormatMapMethod;
    private static MethodHandle applyFontMethodHandle;
    // private static Method applyFontMethod;
    private static MethodHandle buildCTRstMethodHandle;
    // private static Method buildCTRstMethod;

    static {
        try {
            stFeild = XSSFRichTextString.class.getDeclaredField("st");
            stFeild.setAccessible(true);

            /* MethodType rtype0 = MethodType.methodType(TreeMap.class);
            getFormatMapMethodHandle = lookup.findVirtual(XSSFRichTextString.class, "getFormatMap", rtype0); */
            Method getFormatMapMethod = XSSFRichTextString.class.getDeclaredMethod("getFormatMap", CTRst.class);
            getFormatMapMethod.setAccessible(true);
            getFormatMapMethodHandle = lookup.unreflect(getFormatMapMethod);
            /* MethodType rtype1 = MethodType.methodType(void.class);
            applyFontMethodHandle = lookup.findVirtual(XSSFRichTextString.class, "applyFont", rtype1); */
            Method applyFontMethod = XSSFRichTextString.class.getDeclaredMethod("applyFont", TreeMap.class,int.class,int.class,CTRPrElt.class);
            applyFontMethod.setAccessible(true);
            applyFontMethodHandle = lookup.unreflect(applyFontMethod);
            /* MethodType rtype2 = MethodType.methodType(CTRst.class);
            buildCTRstMethodHandle = lookup.findVirtual(XSSFRichTextString.class, "buildCTRst", rtype2); */
            Method buildCTRstMethod = XSSFRichTextString.class.getDeclaredMethod("buildCTRst", String.class, TreeMap.class);
            buildCTRstMethod.setAccessible(true);
            buildCTRstMethodHandle = lookup.unreflect(buildCTRstMethod);

        } catch (NoSuchFieldException | NoSuchMethodException | IllegalAccessException e) {
            throw new RuntimeException(e);
        }
    }


    @Override
    public void append(String text, XSSFFont font) {
        try {
            MethodHandle stGetter = lookup.unreflectGetter(stFeild);
            CTRst st = (CTRst) stGetter.invoke(this);
            if (st.sizeOfRArray() == 0 && st.isSetT()) {
                // convert <t>string</t> into a text run: <r><t>string</t></r>
                CTRElt lt = st.addNewR();
                lt.setT(st.getT());
                preserveSpaces(lt.xgetT());
                st.unsetT();
            }
            CTRElt lt = st.addNewR();
            lt.setT(text);
            preserveSpaces(lt.xgetT());

            if (font != null) {
                CTRPrElt pr = lt.addNewRPr();
                this.setRunAttributes(font.getCTFont(), pr);
            }
        } catch (Throwable e) {
            throw new RuntimeException(e);
        }
    }

    @Override
    public void applyFont(int startIndex, int endIndex, Font font) {
        try {
            MethodHandle stGetter = lookup.unreflectGetter(stFeild);
            CTRst st = (CTRst) stGetter.invoke(this);
            if (startIndex > endIndex)
                throw new IllegalArgumentException("Start index must be less than end index, but had " + startIndex + " and " + endIndex);
            if (startIndex < 0 || endIndex > length())
                throw new IllegalArgumentException("Start and end index not in range, but had " + startIndex + " and " + endIndex);

            if (startIndex == endIndex)
                return;

            if (st.sizeOfRArray() == 0 && st.isSetT()) {
                // convert <t>string</t> into a text run: <r><t>string</t></r>
                st.addNewR().setT(st.getT());
                st.unsetT();
            }

            String text = getString();
            XSSFFont xssfFont = (XSSFFont) font;

            TreeMap<Integer, CTRPrElt> formats = (TreeMap<Integer, CTRPrElt>) getFormatMapMethodHandle.invokeWithArguments(this,st);
            CTRPrElt fmt = CTRPrElt.Factory.newInstance();
            this.setRunAttributes(xssfFont.getCTFont(), fmt);
            applyFontMethodHandle.invoke(this,formats, startIndex, endIndex, fmt);

            CTRst newSt = (CTRst) (buildCTRstMethodHandle.invoke(this,text, formats));
            st.set(newSt);
        } catch (Throwable e) {
            throw new RuntimeException(e);
        }
    }

    private void setRunAttributes(CTFont ctFont, CTRPrElt pr) {
        if (ctFont.sizeOfBArray() > 0 && ctFont.getBArray(0).getVal()) pr.addNewB();
        if (ctFont.sizeOfUArray() > 0) pr.addNewU().setVal(ctFont.getUArray(0).getVal());
        if (ctFont.sizeOfIArray() > 0 && ctFont.getIArray(0).getVal()) pr.addNewI();
        if (ctFont.sizeOfColorArray() > 0) {
            CTColor c1 = ctFont.getColorArray(0);
            CTColor c2 = pr.addNewColor();
            if (c1.isSetAuto()) c2.setAuto(c1.getAuto());
            if (c1.isSetIndexed()) c2.setIndexed(c1.getIndexed());
            if (c1.isSetRgb()) c2.setRgb(c1.getRgb());
            if (c1.isSetTheme()) c2.setTheme(c1.getTheme());
            if (c1.isSetTint()) c2.setTint(c1.getTint());
        }
        if (ctFont.sizeOfSzArray() > 0) pr.addNewSz().setVal(ctFont.getSzArray(0).getVal());
        if (ctFont.sizeOfNameArray() > 0) pr.addNewRFont().setVal(ctFont.getNameArray(0).getVal());
        if (ctFont.sizeOfFamilyArray() > 0) pr.addNewFamily().setVal(ctFont.getFamilyArray(0).getVal());
        if (ctFont.sizeOfSchemeArray() > 0) pr.addNewScheme().setVal(ctFont.getSchemeArray(0).getVal());
        if (ctFont.sizeOfCharsetArray() > 0) pr.addNewCharset().setVal(ctFont.getCharsetArray(0).getVal());

        if (ctFont.sizeOfCondenseArray() > 0 && ctFont.getCondenseArray(0).getVal()) pr.addNewCondense();
        if (ctFont.sizeOfExtendArray() > 0 && ctFont.getExtendArray(0).getVal()) pr.addNewExtend();
        if (ctFont.sizeOfVertAlignArray() > 0) pr.addNewVertAlign().setVal(ctFont.getVertAlignArray(0).getVal());
        if (ctFont.sizeOfOutlineArray() > 0 && ctFont.getOutlineArray(0).getVal()) pr.addNewOutline();
        if (ctFont.sizeOfShadowArray() > 0 && ctFont.getShadowArray(0).getVal()) pr.addNewShadow();
        if (ctFont.sizeOfStrikeArray() > 0 && ctFont.getStrikeArray(0).getVal()) pr.addNewStrike();
    }
}