Remove unneeded toString and valueOf calls (#2230)

* Remove unneeded toString and valueOf calls

Author: elharo

Diff for: compat/maven-artifact/src/main/java/org/apache/maven/artifact/versioning/ComparableVersion.java

@@ -839,8 +839,8 @@ public static void main(String... args) {
 
             if (prev != null) {
                 int compare = prev.compareTo(c);
-                System.out.println("   " + prev.toString() + ' ' + ((compare == 0) ? "==" : ((compare < 0) ? "<" : ">"))
-                        + ' ' + version);
+                System.out.println(
+                        "   " + prev + ' ' + ((compare == 0) ? "==" : ((compare < 0) ? "<" : ">")) + ' ' + version);
             }
 
             System.out.println(

Diff for: compat/maven-compat/src/main/java/org/apache/maven/repository/legacy/DefaultUpdateCheckManager.java

@@ -243,8 +243,8 @@ private void writeLastUpdated(File touchfile, String key, String error) {
             } catch (IOException e) {
                 getLogger()
                         .debug(
-                                "Failed to record lastUpdated information for resolution.\nFile: "
-                                        + touchfile.toString() + "; key: " + key,
+                                "Failed to record lastUpdated information for resolution.\nFile: " + touchfile
+                                        + "; key: " + key,
                                 e);
             } finally {
                 if (lock != null) {

Diff for: compat/maven-embedder/src/main/java/org/apache/maven/cli/transfer/AbstractMavenTransferListener.java

@@ -205,7 +205,7 @@ public void transferInitiated(TransferEvent event) {
         message.append(darkOn).append(": ").append(resource.getRepositoryUrl());
         message.append(darkOff).append(resource.getResourceName());
 
-        out.println(message.toString());
+        out.println(message);
     }
 
     @Override
@@ -242,6 +242,6 @@ public void transferSucceeded(TransferEvent event) {
         }
 
         message.append(')').append(darkOff);
-        out.println(message.toString());
+        out.println(message);
     }
 }

Diff for: compat/maven-plugin-api/src/main/java/org/apache/maven/plugin/logging/SystemStreamLog.java

@@ -108,8 +108,7 @@ public void error(CharSequence content, Throwable error) {
 
         error.printStackTrace(pWriter);
 
-        System.err.println(
-                "[error] " + content.toString() + System.lineSeparator() + System.lineSeparator() + sWriter.toString());
+        System.err.println("[error] " + content + System.lineSeparator() + System.lineSeparator() + sWriter);
     }
 
     /**
@@ -121,7 +120,7 @@ public void error(Throwable error) {
 
         error.printStackTrace(pWriter);
 
-        System.err.println("[error] " + sWriter.toString());
+        System.err.println("[error] " + sWriter);
     }
 
     /**
@@ -163,7 +162,7 @@ private void print(String prefix, Throwable error) {
 
         error.printStackTrace(pWriter);
 
-        System.out.println("[" + prefix + "] " + sWriter.toString());
+        System.out.println("[" + prefix + "] " + sWriter);
     }
 
     private void print(String prefix, CharSequence content, Throwable error) {
@@ -172,7 +171,6 @@ private void print(String prefix, CharSequence content, Throwable error) {
 
         error.printStackTrace(pWriter);
 
-        System.out.println("[" + prefix + "] " + content.toString() + System.lineSeparator() + System.lineSeparator()
-                + sWriter.toString());
+        System.out.println("[" + prefix + "] " + content + System.lineSeparator() + System.lineSeparator() + sWriter);
     }
 }

Diff for: impl/maven-cli/src/main/java/org/apache/maven/cling/transfer/AbstractMavenTransferListener.java

@@ -56,7 +56,7 @@ public void transferInitiated(TransferEvent event) {
         message.style(STYLE).append(": ").append(resource.getRepositoryUrl());
         message.resetStyle().append(resource.getResourceName());
 
-        out.println(message.toString());
+        out.println(message);
     }
 
     @Override
@@ -93,6 +93,6 @@ public void transferSucceeded(TransferEvent event) {
         }
 
         message.append(')').resetStyle();
-        out.println(message.toString());
+        out.println(message);
     }
 }

Diff for: impl/maven-core/src/main/java/org/apache/maven/plugin/DebugConfigurationListener.java

@@ -72,7 +72,7 @@ private String toString(Object obj) {
                 if (i > 0) {
                     buf.append(", ");
                 }
-                buf.append(String.valueOf(Array.get(obj, i)));
+                buf.append(Array.get(obj, i));
             }
             buf.append(']');
             str = buf.toString();

Diff for: impl/maven-impl/src/main/java/org/apache/maven/impl/model/profile/ConditionProfileActivator.java

@@ -133,7 +133,7 @@ public Map<String, ConditionParser.ExpressionFunction> registerFunctions(
                         if (!causeChain.isEmpty()) {
                             causeChain.append(" Caused by: ");
                         }
-                        causeChain.append(cause.toString());
+                        causeChain.append(cause);
                         cause = cause.getCause();
                     }
                     throw new RuntimeException(