Use String#isEmpty()

Author: garydgregory

log4j-1.2-api/src/main/java/org/apache/log4j/PropertyConfigurator.java

@@ -426,7 +426,7 @@ void parseAdditivityForLogger(final Properties properties, final Logger logger,
         final String value = OptionConverter.findAndSubst(ADDITIVITY_PREFIX + loggerName, properties);
         LogLog.debug("Handling " + ADDITIVITY_PREFIX + loggerName + "=[" + value + "]");
         // touch additivity only if necessary
-        if ((value != null) && (!value.equals(""))) {
+        if (value != null && !value.isEmpty()) {
             final boolean additivity = OptionConverter.toBoolean(value, true);
             LogLog.debug("Setting additivity for \"" + loggerName + "\" to " + additivity);
             logger.setAdditivity(additivity);
@@ -581,7 +581,7 @@ void parseCategory(
         // If value is not in the form ", appender.." or "", then we should set
         // the level of the loggeregory.
 
-        if (!(value.startsWith(",") || value.equals(""))) {
+        if (!(value.startsWith(",") || value.isEmpty())) {
 
             // just to be on the safe side...
             if (!st.hasMoreTokens()) {

log4j-1.2-api/src/main/java/org/apache/log4j/config/PropertiesConfiguration.java

@@ -390,7 +390,7 @@ private boolean getAdditivityForLogger(final Properties props, final String logg
         final String value = OptionConverter.findAndSubst(key, props);
         LOGGER.debug("Handling {}=[{}]", key, value);
         // touch additivity only if necessary
-        if ((value != null) && (!value.equals(""))) {
+        if (value != null && !value.isEmpty()) {
             additivity = OptionConverter.toBoolean(value, true);
         }
         return additivity;
@@ -412,7 +412,7 @@ private void parseLogger(
 
         // If value is not in the form ", appender.." or "", then we should set the level of the logger.
 
-        if (!(value.startsWith(",") || value.equals(""))) {
+        if (!(value.startsWith(",") || value.isEmpty())) {
 
             // just to be on the safe side...
             if (!st.hasMoreTokens()) {

log4j-1.2-api/src/main/java/org/apache/log4j/xml/XmlConfiguration.java

@@ -732,14 +732,14 @@ private void parse(Element element) {
         // if the log4j.dtd is not specified in the XML file, then the
         // "debug" attribute is returned as the empty string.
         String status = "error";
-        if (!debugAttrib.equals("") && !debugAttrib.equals("null")) {
+        if (!debugAttrib.isEmpty() && !debugAttrib.equals("null")) {
             status = OptionConverter.toBoolean(debugAttrib, true) ? "debug" : "error";
         } else {
             LOGGER.debug("Ignoring " + INTERNAL_DEBUG_ATTR + " attribute.");
         }
 
         final String confDebug = subst(element.getAttribute(CONFIG_DEBUG_ATTR));
-        if (!confDebug.equals("") && !confDebug.equals("null")) {
+        if (!confDebug.isEmpty() && !confDebug.equals("null")) {
             LOGGER.warn("The \"" + CONFIG_DEBUG_ATTR + "\" attribute is deprecated.");
             LOGGER.warn("Use the \"" + INTERNAL_DEBUG_ATTR + "\" attribute instead.");
             status = OptionConverter.toBoolean(confDebug, true) ? "debug" : "error";