fixes #525 (#530)

* fixes #525

* Simply unit test.

src/main/java/net/sf/jsqlparser/expression/TimestampValue.java

@@ -29,9 +29,17 @@
 public class TimestampValue implements Expression {
 
     private Timestamp value;
-
+    private char quotation = '\'';
     public TimestampValue(String value) {
-        this.value = Timestamp.valueOf(value.substring(1, value.length() - 1));
+        if (value == null) {
+            throw new java.lang.IllegalArgumentException("null string");
+        } else {
+            if (value.charAt(0) == quotation) {
+                this.value = Timestamp.valueOf(value.substring(1, value.length() - 1));
+            } else {
+                this.value = Timestamp.valueOf(value.substring(0, value.length()));
+            }
+        }
     }
 
     @Override

src/test/java/net/sf/jsqlparser/expression/TimestampValueTest.java

@@ -0,0 +1,31 @@
+package net.sf.jsqlparser.expression;
+
+import net.sf.jsqlparser.JSQLParserException;
+import org.junit.Test;
+
+import java.text.DateFormat;
+import java.text.SimpleDateFormat;
+import java.util.Date;
+import java.util.Locale;
+
+/**
+ * @author Linyu Chen
+ */
+public class TimestampValueTest {
+
+    @Test
+    public void testTimestampValue_issue525() throws JSQLParserException {
+        DateFormat dateFormat = new SimpleDateFormat("yyyy-MM-dd HH:mm:ss", Locale.getDefault());
+        String currentDate = dateFormat.format(new Date());
+        TimestampValue tv = new TimestampValue(currentDate);
+        System.out.println(tv.toString());
+    }
+
+    @Test
+    public void testTimestampValueWithQuotation_issue525() throws JSQLParserException {
+        DateFormat dateFormat = new SimpleDateFormat("yyyy-MM-dd HH:mm:ss", Locale.getDefault());
+        String currentDate = dateFormat.format(new Date());
+        TimestampValue tv = new TimestampValue("'" + currentDate + "'");
+        System.out.println(tv.toString());
+    }
+}