Create ImageType.java

src/main/java/vip/xumy/core/utils/ImageType.java

@@ -0,0 +1,42 @@
+package vip.xumy.core.utils;
+
+import lombok.Getter;
+
+public enum ImageType {
+	PNG('P', 'N', 'G', '-', "png"), JPG('J', 'F', 'I', 'F', "jpg"), GIF('G', 'I', 'F', '-', "gif");
+	@Getter
+	private char begin, mid, end, last;
+	@Getter
+	private String type;
+
+	private ImageType(char begin, char mid, char end, char last, String type) {
+		this.begin = begin;
+		this.mid = mid;
+		this.end = end;
+		this.last = last;
+		this.type = type;
+	}
+
+	/**
+	 * 获取图片类型
+	 * 
+	 * @param data
+	 * @return
+	 */
+	public static ImageType getImageType(byte[] data) {
+		// Png:
+		if (PNG.getBegin() == data[1] && PNG.getMid() == data[2] && PNG.getEnd() == data[3]) {
+			return PNG;
+		}
+		// Gif:
+		if (GIF.getBegin() == data[0] && GIF.getMid() == data[1] && GIF.getEnd() == data[2]) {
+			return GIF;
+		}
+		// JPG:
+		if (JPG.getBegin() == data[6] && JPG.getMid() == data[7] && JPG.getEnd() == data[8]
+				&& JPG.getLast() == data[9]) {
+			return JPG;
+		}
+		return null;
+	}
+}