fix: modified what pointed out

Author: sttk

src/main/java/com/github/sttk/errs/Exc.java

@@ -106,7 +106,7 @@ public Object getReason() {
      */
     @Override
     public String getMessage() {
-        return new StringBuilder(this.reason.getClass().getName()).append(" ").append(reason.toString()).toString();
+        return reason.toString();
     }
 
     /**
@@ -118,7 +118,7 @@ public String getMessage() {
     @Override
     public String toString() {
         var buf = new StringBuilder(getClass().getName());
-        buf.append(" { reason = ").append(getMessage());
+        buf.append(" { reason = ").append(reason.getClass().getName()).append(" ").append(reason.toString());
         buf.append(", file = ").append(this.trace.getFileName());
         buf.append(", line = ").append(this.trace.getLineNumber());
         if (getCause() != null) {

src/test/java/com/github/sttk/errs/ExcTest.java

@@ -201,16 +201,14 @@ class TestGetMessage {
         @Test
         void with_cause() {
             var exc = new Exc(new IndexOutOfRange("data", 4, 0, 3));
-            assertThat(exc.getMessage()).isEqualTo(
-                    "com.github.sttk.errs.ExcTest$IndexOutOfRange IndexOutOfRange[name=data, index=4, min=0, max=3]");
+            assertThat(exc.getMessage()).isEqualTo("IndexOutOfRange[name=data, index=4, min=0, max=3]");
         }
 
         @Test
         void with_no_cause() {
             var cause = new IndexOutOfBoundsException(4);
             var exc = new Exc(new IndexOutOfRange("data", 4, 0, 3), cause);
-            assertThat(exc.getMessage()).isEqualTo(
-                    "com.github.sttk.errs.ExcTest$IndexOutOfRange IndexOutOfRange[name=data, index=4, min=0, max=3]");
+            assertThat(exc.getMessage()).isEqualTo("IndexOutOfRange[name=data, index=4, min=0, max=3]");
         }
     }
 
@@ -220,15 +218,15 @@ class TestToString {
         void with_reason() {
             var exc = new Exc(new IndexOutOfRange("data", 4, 0, 3));
             assertThat(exc.toString()).isEqualTo(
-                    "com.github.sttk.errs.Exc { reason = com.github.sttk.errs.ExcTest$IndexOutOfRange IndexOutOfRange[name=data, index=4, min=0, max=3], file = ExcTest.java, line = 221 }");
+                    "com.github.sttk.errs.Exc { reason = com.github.sttk.errs.ExcTest$IndexOutOfRange IndexOutOfRange[name=data, index=4, min=0, max=3], file = ExcTest.java, line = 219 }");
         }
 
         @Test
         void with_reason_and_cause() {
             var cause = new IndexOutOfBoundsException(4);
             var exc = new Exc(new IndexOutOfRange("data", 4, 0, 3), cause);
             assertThat(exc.toString()).isEqualTo(
-                    "com.github.sttk.errs.Exc { reason = com.github.sttk.errs.ExcTest$IndexOutOfRange IndexOutOfRange[name=data, index=4, min=0, max=3], file = ExcTest.java, line = 229, cause = java.lang.IndexOutOfBoundsException: Index out of range: 4 }");
+                    "com.github.sttk.errs.Exc { reason = com.github.sttk.errs.ExcTest$IndexOutOfRange IndexOutOfRange[name=data, index=4, min=0, max=3], file = ExcTest.java, line = 227, cause = java.lang.IndexOutOfBoundsException: Index out of range: 4 }");
         }
     }
 
@@ -238,8 +236,7 @@ class TestToRuntimeException {
         void getMessage() {
             var exc = new Exc(new IndexOutOfRange("data", 4, 0, 3));
             var rtExc = exc.toRuntimeException();
-            assertThat(rtExc.getMessage()).isEqualTo(
-                    "com.github.sttk.errs.ExcTest$IndexOutOfRange IndexOutOfRange[name=data, index=4, min=0, max=3]");
+            assertThat(rtExc.getMessage()).isEqualTo("IndexOutOfRange[name=data, index=4, min=0, max=3]");
         }
 
         @Test