add source code for dynamic compile

hutool-core/src/main/java/cn/hutool/core/compiler/JavaSourceFileObject.java

@@ -28,6 +28,11 @@ class JavaSourceFileObject extends SimpleJavaFileObject {
 	 */
 	private InputStream inputStream;
 
+	/**
+	 * Source code.
+	 */
+	private String sourceCode;
+
 	/**
 	 * 构造，支持File等路径类型的源码
 	 *
@@ -82,9 +87,12 @@ class JavaSourceFileObject extends SimpleJavaFileObject {
 	 */
 	@Override
 	public CharSequence getCharContent(boolean ignoreEncodingErrors) throws IOException {
+		if (sourceCode == null) {
 			try(final InputStream in = openInputStream()){
-			return IoUtil.readUtf8(in);
+				sourceCode = IoUtil.readUtf8(in);
 			}
 		}
+		return sourceCode;
+	}
 
 }

hutool-core/src/test/java/cn/hutool/core/compiler/JavaSourceCompilerTest.java

@@ -40,4 +40,17 @@ public class JavaSourceCompilerTest {
 		Assert.assertTrue(String.valueOf(obj).startsWith("c.C@"));
 	}
 
+	@Test
+	public void testErrorCompile() {
+		Exception exception = null;
+		try {
+			CompilerUtil.getCompiler(null)
+					.addSource(FileUtil.file("test-compile/error/ErrorClazz.java"))
+					.compile();
+		} catch (Exception ex) {
+			exception = ex;
+		} finally {
+			Assert.assertTrue(exception instanceof CompilerException);
+		}
+	}
 }

hutool-core/src/test/resources/test-compile/error/ErrorClazz.java

@@ -0,0 +1,8 @@
+package error;
+
+public class ErrorClazz {
+
+	public static void 123main(String[] args) {
+		System.out.println("hello world");
+	}
+}