编译模板时删除并未实际使用的field

src/main/java/com/uas/report/service/impl/PrintServiceImpl.java

@@ -1,7 +1,9 @@
 package com.uas.report.service.impl;
 
+import java.io.BufferedReader;
 import java.io.ByteArrayOutputStream;
 import java.io.File;
+import java.io.FileReader;
 import java.io.FileWriter;
 import java.io.IOException;
 import java.io.OutputStream;
@@ -12,8 +14,12 @@ import java.sql.ResultSetMetaData;
 import java.sql.SQLException;
 import java.util.ArrayList;
 import java.util.HashMap;
+import java.util.HashSet;
 import java.util.List;
 import java.util.Map;
+import java.util.Set;
+import java.util.regex.Matcher;
+import java.util.regex.Pattern;
 
 import javax.sql.DataSource;
 
@@ -313,25 +319,25 @@ public class PrintServiceImpl implements PrintService {
 			// 如果查询语句中含有WHERE_CONDITION参数，需将其替换掉
 			if (queryString.contains("$P!{WHERE_CONDITION}")) {
 				queryString = queryString.substring(0, queryString.indexOf("$P!{WHERE_CONDITION}"))
-						+ "where rownum = 1";
+						+ "where rownum = 0";
 			}
 			// 如果查询语句中含有where条件，则可能有用到一些参数，需将其替换掉
 			else if (queryString.toUpperCase().contains("WHERE")) {
-				queryString = queryString.substring(0, queryString.indexOf("WHERE")) + "where rownum = 1";
+				queryString = queryString.substring(0, queryString.indexOf("WHERE")) + "where rownum = 0";
 			}
 			List<String> columnNames = getColumnNames(connection, queryString);
 			if (CollectionUtils.isEmpty(columnNames)) {
 				throw new ReportException("未查询到任何列：" + queryString);
 			}
+			Set<String> usedFields = getUsedFields(jrxmlFilePath);
 			// 指定的field
-			@SuppressWarnings("rawtypes")
-			List fieldElements = rootElement.elements("field");
+			@SuppressWarnings("unchecked")
+			List<Element> elements = rootElement.elements("field");
 			boolean needModifying = false;
-			for (int i = 0; i < fieldElements.size(); i++) {
-				Element element = (Element) fieldElements.get(i);
+			for (Element element : elements) {
 				String columnName = element.attribute("name").getText();
-				// 如果指定的Field在当前帐套的表中不存在，则删除该Field
-				if (!columnNames.contains(columnName.toUpperCase())) {
+				// 如果指定的Field在当前帐套的表中不存在，或者在模板中并未实际使用，则删除该Field
+				if (!columnNames.contains(columnName.toUpperCase()) || !usedFields.contains(columnName.toUpperCase())) {
 					needModifying = true;
 					rootElement.remove(element);
 					logger.info("Removed... " + columnName);
@@ -375,6 +381,29 @@ public class PrintServiceImpl implements PrintService {
 		return result;
 	}
 
+	/**
+	 * 获取模板中实际使用的Field
+	 * 
+	 * @param jrxmlFilePath
+	 * @return
+	 * @throws IOException
+	 */
+	private Set<String> getUsedFields(String jrxmlFilePath) throws IOException {
+		BufferedReader bufferedReader = new BufferedReader(new FileReader(jrxmlFilePath));
+		String line = null;
+		Set<String> result = new HashSet<>();
+		while (!StringUtils.isEmpty((line = bufferedReader.readLine()))) {
+			// 格式为$F{PD_TOTAL}
+			Pattern pattern = Pattern.compile("\\$F\\{([^\\$]*)\\}");
+			Matcher matcher = pattern.matcher(line);
+			while (matcher.find()) {
+				result.add(matcher.group(1));
+			}
+		}
+		bufferedReader.close();
+		return result;
+	}
+
 	/**
 	 * 以xls的格式导出报表
 	 *