string.equals("") -> string.isEmpty() or "".equals(string)

git-svn-id: https://svn.apache.org/repos/asf/poi/trunk@1812463 13f79535-47bb-0310-9956-ffa450edef68

src/examples/jsp/HSSFExample.jsp

@@ -32,7 +32,7 @@ Select an Excel file to read.
 
 <%
 	String filename = request.getParameter("xls_filename"); 
-	if (filename != null && !filename.equals("")) {
+	if (filename != null && !filename.isEmpty()) {
 %>	
 	<br>You chose the file <%= filename %>. 
 	<br><br>It's contents are: 	

src/examples/src/org/apache/poi/ss/examples/html/ToHtml.java

@@ -479,7 +479,7 @@ public class ToHtml {
                                 style.getDataFormatString());
                         CellFormatResult result = cf.apply(cell);
                         content = result.text;
-                        if (content.equals("")) {
+                        if ("".equals(content)) {
                             content = " ";
                         }
                     }

src/java/org/apache/poi/hssf/usermodel/EscherGraphics.java

@@ -296,7 +296,7 @@ public class EscherGraphics extends Graphics
     @Override
     public void drawString(String str, int x, int y)
     {
-        if (str == null || str.equals(""))
+        if (str == null || str.isEmpty())
             return;
 
         Font excelFont = font;

src/java/org/apache/poi/ss/format/CellFormatPart.java

@@ -328,7 +328,7 @@ public class CellFormatPart {
      */
     private CellFormatType formatType(String fdesc) {
         fdesc = fdesc.trim();
-        if (fdesc.equals("") || fdesc.equalsIgnoreCase("General"))
+        if (fdesc.isEmpty() || fdesc.equalsIgnoreCase("General"))
             return CellFormatType.GENERAL;
 
         Matcher m = SPECIFICATION_PAT.matcher(fdesc);

src/java/org/apache/poi/ss/formula/functions/DGet.java

@@ -61,7 +61,7 @@ public final class DGet implements IDStarAlgorithm {
             return ErrorEval.VALUE_INVALID;
         } else
             try {
-                if(OperandResolver.coerceValueToString(OperandResolver.getSingleValue(result, 0, 0)).equals("")) {
+                if(OperandResolver.coerceValueToString(OperandResolver.getSingleValue(result, 0, 0)).isEmpty()) {
                     return ErrorEval.VALUE_INVALID;
                 }
                 else {

src/ooxml/java/org/apache/poi/openxml4j/opc/OPCPackage.java

@@ -847,7 +847,7 @@ public abstract class OPCPackage implements RelationshipSource, Closeable {
 			throw new IllegalArgumentException("partName");
 		}
 
-		if (contentType == null || contentType.equals("")) {
+		if (contentType == null || contentType.isEmpty()) {
 			throw new IllegalArgumentException("contentType");
 		}
 

src/ooxml/java/org/apache/poi/openxml4j/opc/PackagePartCollection.java

@@ -56,7 +56,7 @@ public final class PackagePartCollection implements Serializable {
 				PackagingURIHelper.FORWARD_SLASH_STRING);
 		StringBuilder concatSeg = new StringBuilder();
 		for (String seg : segments) {
-			if (!seg.equals(""))
+			if (!seg.isEmpty())
 				concatSeg.append(PackagingURIHelper.FORWARD_SLASH_CHAR);
 			concatSeg.append(seg);
 			if (this.registerPartNameStr.contains(concatSeg.toString())) {

src/ooxml/java/org/apache/poi/openxml4j/opc/PackagePartName.java

@@ -241,14 +241,14 @@ public final class PackagePartName implements Comparable<PackagePartName> {
 
 		// Split the URI into several part and analyze each
 		String[] segments = partUri.toASCIIString().split("/");
-		if (segments.length <= 1 || !segments[0].equals(""))
+		if (segments.length <= 1 || !segments[0].isEmpty())
 			throw new InvalidFormatException(
 					"A part name shall not have empty segments [M1.3]: "
 							+ partUri.getPath());
 
 		for (int i = 1; i < segments.length; ++i) {
 			String seg = segments[i];
-			if (seg == null || "".equals(seg)) {
+			if (seg == null || seg.isEmpty()) {
 				throw new InvalidFormatException(
 						"A part name shall not have empty segments [M1.3]: "
 								+ partUri.getPath());

src/ooxml/java/org/apache/poi/openxml4j/opc/PackagingURIHelper.java

@@ -35,6 +35,9 @@ import org.apache.poi.util.POILogger;
  * @version 0.1
  */
 public final class PackagingURIHelper {
+    // FIXME: this class implements a lot of path joining and splitting logic that
+    // is already implemented in java.nio.file.Path.
+    // This class should heavily leverage Java library code to reduce the number of lines of code that POI has to maintain and test
     private final static POILogger _logger = POILogFactory.getLogger(PackagingURIHelper.class);
 
 	/**
@@ -321,13 +324,13 @@ public final class PackagingURIHelper {
 
 		// If we didn't have a good match or at least except a first empty element
 		if ((segmentsTheSame == 0 || segmentsTheSame == 1) &&
-				segmentsSource[0].equals("") && segmentsTarget[0].equals("")) {
+				segmentsSource[0].isEmpty() && segmentsTarget[0].isEmpty()) {
 			for (int i = 0; i < segmentsSource.length - 2; i++) {
 				retVal.append("../");
 			}
 			for (int i = 0; i < segmentsTarget.length; i++) {
-				if (segmentsTarget[i].equals(""))
-					continue;
+				if (segmentsTarget[i].isEmpty())
+					continue;i
 				retVal.append(segmentsTarget[i]);
 				if (i != segmentsTarget.length - 1)
 					retVal.append("/");

src/ooxml/java/org/apache/poi/openxml4j/opc/internal/PackagePropertiesPart.java

@@ -566,7 +566,7 @@ public final class PackagePropertiesPart extends PackagePart implements
 	 * Convert a strig value into a Nullable<String>
 	 */
 	private Nullable<String> setStringValue(String s) {
-		if (s == null || s.equals("")) {
+		if (s == null || s.isEmpty()) {
 			return new Nullable<>();
 		}
 		return new Nullable<>(s);
@@ -579,7 +579,7 @@ public final class PackagePropertiesPart extends PackagePart implements
 	 *             Throws if the date format isnot valid.
 	 */
 	private Nullable<Date> setDateValue(String dateStr) throws InvalidFormatException {
-		if (dateStr == null || dateStr.equals("")) {
+		if (dateStr == null || dateStr.isEmpty()) {
 			return new Nullable<>();
 		}
 

src/ooxml/java/org/apache/poi/xssf/extractor/XSSFExportToXml.java

@@ -382,7 +382,7 @@ public class XSSFExportToXml implements Comparator<String>{
 
     private boolean isNamespaceDeclared() {
         String schemaNamespace = getNamespace();
-        return schemaNamespace!=null && !schemaNamespace.equals("");
+        return schemaNamespace!=null && !schemaNamespace.isEmpty();
     }
 
     private String getNamespace() {

src/ooxml/testcases/org/apache/poi/xssf/extractor/TestXSSFExportToXML.java

@@ -76,7 +76,7 @@ public final class TestXSSFExportToXML {
 			String xml = os.toString("UTF-8");
 
 			assertNotNull(xml);
-			assertFalse(xml.equals(""));
+			assertFalse(xml.isEmpty());
 
 			String docente = xml.split("<DOCENTE>")[1].split("</DOCENTE>")[0].trim();
 			String nome = xml.split("<NOME>")[1].split("</NOME>")[0].trim();
@@ -124,7 +124,7 @@ public final class TestXSSFExportToXML {
 			String xml = os.toString("UTF-8");
 
 			assertNotNull(xml);
-			assertFalse(xml.equals(""));
+			assertFalse(xml.isEmpty());
 
 			String docente = xml.split("<DOCENTE>")[1].split("</DOCENTE>")[0].trim();
 			String nome = xml.split("<NOME>")[1].split("</NOME>")[0].trim();
@@ -256,7 +256,7 @@ public final class TestXSSFExportToXML {
             String xmlData = os.toString("UTF-8");
 
             assertNotNull(xmlData);
-            assertFalse(xmlData.equals(""));
+            assertFalse(xmlData.isEmpty());
 
             String a = xmlData.split("<A>")[1].split("</A>")[0].trim();
             String b = a.split("<B>")[1].split("</B>")[0].trim();
@@ -299,7 +299,7 @@ public final class TestXSSFExportToXML {
             String xmlData = os.toString("UTF-8");
 
             assertNotNull(xmlData);
-            assertFalse(xmlData.equals(""));
+            assertFalse(xmlData.isEmpty());
 
             assertEquals("2012-01-13", xmlData.split("<DATE>")[1].split("</DATE>")[0].trim());
             assertEquals("2012-02-16", xmlData.split("<FORMULA_DATE>")[1].split("</FORMULA_DATE>")[0].trim());
@@ -333,7 +333,7 @@ public final class TestXSSFExportToXML {
             String xmlData = os.toString("UTF-8");
 
             assertNotNull(xmlData);
-            assertFalse(xmlData.equals(""));
+            assertFalse(xmlData.isEmpty());
 
             String a = xmlData.split("<A>")[1].split("</A>")[0].trim();
             String doubleValue = a.split("<DOUBLE>")[1].split("</DOUBLE>")[0].trim();
@@ -372,7 +372,7 @@ public final class TestXSSFExportToXML {
            String xmlData = os.toString("UTF-8");
 
            assertNotNull(xmlData);
-           assertFalse(xmlData.equals(""));
+           assertFalse(xmlData.isEmpty());
 
            String a = xmlData.split("<A>")[1].split("</A>")[0].trim();
            String euro = a.split("<EUR>")[1].split("</EUR>")[0].trim();
@@ -397,7 +397,7 @@ public final class TestXSSFExportToXML {
            String xmlData = os.toString("UTF-8");
 
            assertNotNull(xmlData);
-           assertTrue(!xmlData.equals(""));
+           assertTrue(!xmlData.isEmpty());
 
            String a = xmlData.split("<A>")[1].split("</A>")[0].trim();
            String a_b = a.split("<B>")[1].split("</B>")[0].trim();
@@ -472,7 +472,7 @@ public final class TestXSSFExportToXML {
            String xmlData = os.toString("UTF-8");
 
            assertNotNull(xmlData);
-           assertFalse(xmlData.equals(""));
+           assertFalse(xmlData.isEmpty());
            
            String a = xmlData.split("<A>")[1].split("</A>")[0].trim();
            String a_b = a.split("<B>")[1].split("</B>")[0].trim();
@@ -569,7 +569,7 @@ public final class TestXSSFExportToXML {
            String xmlData = os.toString("UTF-8");
 
            assertNotNull(xmlData);
-           assertFalse(xmlData.equals(""));
+           assertFalse(xmlData.isEmpty());
            
            parseXML(xmlData);
            
@@ -600,7 +600,7 @@ public final class TestXSSFExportToXML {
            String xmlData = os.toString("UTF-8");
 
            assertNotNull(xmlData);
-           assertFalse(xmlData.equals(""));
+           assertFalse(xmlData.isEmpty());
            
            parseXML(xmlData);
            
@@ -631,7 +631,7 @@ public final class TestXSSFExportToXML {
            String xmlData = os.toString("UTF-8");
            
            assertNotNull(xmlData);
-           assertFalse(xmlData.equals(""));
+           assertFalse(xmlData.isEmpty());
            
            assertEquals("2014-12-31", xmlData.split("<DATE>")[1].split("</DATE>")[0].trim());
            assertEquals("12.5", xmlData.split("<REFELEMENT>")[1].split("</REFELEMENT>")[0].trim());

src/testcases/org/apache/poi/ss/usermodel/BaseTestCell.java

@@ -505,7 +505,7 @@ public abstract class BaseTestCell {
         assertEquals("abc", cellA1.getStringCellValue());
 
         fe.evaluateInCell(cellA1);
-        assertFalse("Identified bug with writing back formula result of type string", cellA1.getStringCellValue().equals(""));
+        assertFalse("Identified bug with writing back formula result of type string", cellA1.getStringCellValue().isEmpty());
         assertEquals("abc", cellA1.getStringCellValue());
         
         wb.close();