POI-tl 知识整理：整理5 -＞开发一个插件

实现一个插件就是要告诉我们在模板的某个地方用某些数据做某些事情，我们可以通过实现RenderPolicy接口开发自己的插件

模板

1 写一个将标签替换为Hello, world的插件

import com.deepoove.poi.XWPFTemplate;
import com.deepoove.poi.policy.RenderPolicy;
import com.deepoove.poi.template.ElementTemplate;
import com.deepoove.poi.template.run.RunTemplate;
import org.apache.poi.xwpf.usermodel.XWPFRun;public class HelloWorldRenderPolicy implements RenderPolicy {@Overridepublic void render(ElementTemplate elementTemplate, Object o, XWPFTemplate xwpfTemplate) {XWPFRun run = ((RunTemplate) elementTemplate).getRun();String text = "Hello World!";run.setText(text, 0);}
}

测试就跟下方自定义插件生成表格一起了，继续往下学习！！

2 写一个更复杂的插件，在模板标签位置完完全全使用代码创建一个表格

poi-tl提供了抽象模板类 AbstractRenderPolicy ，它定义了一些骨架步骤并且将数据模型的校验和渲染逻辑分开，使用泛型约束数据类型，让插件开发起来更简单，AbstractRenderPolicy实现地也是RenderPolicy接口

import com.deepoove.poi.data.style.BorderStyle;
import com.deepoove.poi.data.style.Style;
import com.deepoove.poi.policy.AbstractRenderPolicy;
import com.deepoove.poi.policy.TableRenderPolicy;
import com.deepoove.poi.render.RenderContext;
import com.deepoove.poi.util.TableTools;
import com.deepoove.poi.util.UnitUtils;
import com.deepoove.poi.xwpf.BodyContainer;
import com.deepoove.poi.xwpf.BodyContainerFactory;
import org.apache.poi.xwpf.usermodel.XWPFParagraph;
import org.apache.poi.xwpf.usermodel.XWPFRun;
import org.apache.poi.xwpf.usermodel.XWPFTable;public class CustomTableRenderPolicy extends AbstractRenderPolicy<Object> {@Overrideprotected void afterRender(RenderContext<Object> renderContext) {// 清空模板标签所在的段落clearPlaceholder(renderContext, true);}@Overridepublic void doRender(RenderContext<Object> renderContext) throws Exception {// 自定义渲染逻辑XWPFRun run = renderContext.getRun();BodyContainer bodyContainer = BodyContainerFactory.getBodyContainer(run);// 定义行列int row = 10;int col = 8;XWPFTable table = bodyContainer.insertNewTable(run, row, col);XWPFParagraph paragraph = bodyContainer.insertNewParagraph(run);XWPFRun paragraphRun = paragraph.createRun();paragraphRun.setText("自定义表格");paragraphRun.setColor("0000FF");Style style = new Style();style.setFontSize(18);// 表格宽度TableTools.setWidth(table, UnitUtils.cm2Twips(14.63f) + "", null);// 表格边框和样式TableTools.borderTable(table, BorderStyle.DEFAULT);TableTools.mergeCellsHorizonal(table, 0, 0, 7);TableTools.mergeCellsVertically(table, 1, 1, 9);}
}

3 测试

    @Testpublic void testPlugins() throws Exception {CustomTableRenderPolicy policy = new CustomTableRenderPolicy();HelloWorldRenderPolicy policy1 = new HelloWorldRenderPolicy();Configure config = Configure.builder().bind("report", policy).bind("title",policy1).build();XWPFTemplate template = XWPFTemplate.compile("D:\\Idea-projects\\POI_word\\templates_Plugins.docx",config);Map<String, Object> map = new HashMap<>();XWPFTemplate render = template.render(map);FileOutputStream fileOutputStream = new FileOutputStream("D:\\Idea-projects\\POI_word\\output_Plugins.docx");template.writeAndClose(fileOutputStream);template.close();  // 一定要记得关闭}