如何将Image对象进行base64编码 如何将Image对象进行base64编码,不是文件,不能把对象保存成文件。 解决方案 » 免费领取超大流量手机卡,每月29元包185G流量+100分钟通话, 中国电信官方发货 package lab.sodino.base64;import javax.microedition.lcdui.Canvas;import javax.microedition.lcdui.Display;import javax.microedition.lcdui.Graphics;import javax.microedition.lcdui.Image;import javax.microedition.midlet.MIDlet;import javax.microedition.midlet.MIDletStateChangeException;/** @author sodino */public class Base64Test extends MIDlet { protected void destroyApp(boolean unconditional) throws MIDletStateChangeException { } protected void pauseApp() { } protected void startApp() throws MIDletStateChangeException { Display.getDisplay(this).setCurrent(new MyCanvas()); } private class MyCanvas extends Canvas { private Image instanceImg; public MyCanvas() { //创建原始图片 Image originalImg = createInstanceImg(); //获取图片int数据数组 int[] data = new int[originalImg.getWidth() * originalImg.getHeight()]; originalImg.getRGB(data, 0, originalImg.getWidth(), 0, 0, originalImg.getWidth(), originalImg.getHeight()); //转化为byte数组 byte[] byteData = convertIntToByte(data); //Base64 encode String baseEncode = Base64.encode(byteData); //Base64 decode byte[] byteArr = Base64.decode(baseEncode); //恢复图片数据 int[] dataArr = convertByteToInt(byteArr); //恢复图片 instanceImg = Image.createRGBImage(dataArr, originalImg.getWidth(), originalImg.getHeight(), true); } private byte[] convertIntToByte(int[] data) { if (data == null) { return null; } byte[] byteArr = new byte[data.length << 2]; for (int i = 0; i < data.length; i++) { int num = data[i]; byteArr[i * 4 + 0] = (byte) (num >>> 0); byteArr[i * 4 + 1] = (byte) (num >>> 8); byteArr[i * 4 + 2] = (byte) (num >>> 16); byteArr[i * 4 + 3] = (byte) (num >>> 24); } return byteArr; } private int[] convertByteToInt(byte[] byteArr) { if (byteArr == null || byteArr.length == 0 || byteArr.length % 4 != 0) { return null; } int[] data = new int[byteArr.length >> 2]; for (int i = 0; i < data.length; i++) { data[i] = ((int) (byteArr[i * 4 + 0] << 0)) | ((int) (byteArr[i * 4 + 1] << 8)) | ((int) (byteArr[i * 4 + 2] << 16)) | ((int) (byteArr[i * 4 + 3] << 24)); } return data; } private Image createInstanceImg() { int length = 200; int padding = 30; Image img = Image.createImage(length, length); Graphics g = img.getGraphics(); g.setColor(0xff0000); g.fillRect(0, 0, length, length); g.setColor(0xffff00); g.drawString("Base64Test", length >> 1, length >> 1, Graphics.HCENTER | Graphics.TOP); g.drawString("Base64Test", length >> 1, length >> 1 + padding, Graphics.HCENTER | Graphics.TOP); return img; } protected void paint(Graphics g) { g.setColor(0xffffff); g.fillRect(0, 0, 240, 320); g.drawImage(instanceImg, 0, 0, 0); } }}package lab.sodino.base64;import java.io.ByteArrayOutputStream;/** * base64 format encoding & decoding */public class Base64 { private static char[] base64EncodeChars = new char[] { 'A', 'B', 'C', 'D', 'E', 'F', 'G', 'H', 'I', 'J', 'K', 'L', 'M', 'N', 'O', 'P', 'Q', 'R', 'S', 'T', 'U', 'V', 'W', 'X', 'Y', 'Z', 'a', 'b', 'c', 'd', 'e', 'f', 'g', 'h', 'i', 'j', 'k', 'l', 'm', 'n', 'o', 'p', 'q', 'r', 's', 't', 'u', 'v', 'w', 'x', 'y', 'z', '0', '1', '2', '3', '4', '5', '6', '7', '8', '9', '+', '/' }; private static byte[] base64DecodeChars = new byte[] { -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, 62, -1, -1, -1, 63, 52, 53, 54, 55, 56, 57, 58, 59, 60, 61, -1, -1, -1, -1, -1, -1, -1, 0, 1, 2, 3, 4, 5, 6, 7, 8, 9, 10, 11, 12, 13, 14, 15, 16, 17, 18, 19, 20, 21, 22, 23, 24, 25, -1, -1, -1, -1, -1, -1, 26, 27, 28, 29, 30, 31, 32, 33, 34, 35, 36, 37, 38, 39, 40, 41, 42, 43, 44, 45, 46, 47, 48, 49, 50, 51, -1, -1, -1, -1, -1 }; private Base64() { } public static String encode(byte[] data) { StringBuffer sb = new StringBuffer(); int len = data.length; int i = 0; int b1, b2, b3; while (i < len) { b1 = data[i++] & 0xff; if (i == len) { sb.append(base64EncodeChars[b1 >>> 2]); sb.append(base64EncodeChars[(b1 & 0x3) << 4]); sb.append("=="); break; } b2 = data[i++] & 0xff; if (i == len) { sb.append(base64EncodeChars[b1 >>> 2]); sb.append(base64EncodeChars[((b1 & 0x03) << 4) | ((b2 & 0xf0) >>> 4)]); sb.append(base64EncodeChars[(b2 & 0x0f) << 2]); sb.append("="); break; } b3 = data[i++] & 0xff; sb.append(base64EncodeChars[b1 >>> 2]); sb.append(base64EncodeChars[((b1 & 0x03) << 4) | ((b2 & 0xf0) >>> 4)]); sb.append(base64EncodeChars[((b2 & 0x0f) << 2) | ((b3 & 0xc0) >>> 6)]); sb.append(base64EncodeChars[b3 & 0x3f]); } return sb.toString(); } public static byte[] decode(String str) { byte[] data = str.getBytes(); int len = data.length; ByteArrayOutputStream buf = new ByteArrayOutputStream(len); int i = 0; int b1, b2, b3, b4; while (i < len) { /* b1 */ do { b1 = base64DecodeChars[data[i++]]; } while (i < len && b1 == -1); if (b1 == -1) { break; } /* b2 */ do { b2 = base64DecodeChars[data[i++]]; } while (i < len && b2 == -1); if (b2 == -1) { break; } buf.write((int) ((b1 << 2) | ((b2 & 0x30) >>> 4))); /* b3 */ do { b3 = data[i++]; if (b3 == 61) { return buf.toByteArray(); } b3 = base64DecodeChars[b3]; } while (i < len && b3 == -1); if (b3 == -1) { break; } buf.write((int) (((b2 & 0x0f) << 4) | ((b3 & 0x3c) >>> 2))); /* b4 */ do { b4 = data[i++]; if (b4 == 61) { return buf.toByteArray(); } b4 = base64DecodeChars[b4]; } while (i < len && b4 == -1); if (b4 == -1) { break; } buf.write((int) (((b3 & 0x03) << 6) | b4)); } return buf.toByteArray(); }}粗糙地写了一下,看下是不是楼主想要的 给了我很大的启发,但是我的Image对象是java.awt下的,没有你的那个microedition包的对象函数功能。 晕,那你发j2me区来干嘛!! j2se下我也不大懂,不好意思了啊 用ImageIO写到一个ByteOutStream里,取得byte[],然后用base64编码 apache commons-coder包里有。 org.apache.commons.codec.binary.Base64lz自己看下。 在线求教,怎么都编译不过去,头昏 字符进行四则运算时是使用字符编码进行运算 2个方法的结果怎么不一样 能帮说明一下么? return的用法 请问有没有哪位朋友做过俄罗斯方块的程序? 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package lab.sodino.base64;import javax.microedition.lcdui.Canvas;
import javax.microedition.lcdui.Display;
import javax.microedition.lcdui.Graphics;
import javax.microedition.lcdui.Image;
import javax.microedition.midlet.MIDlet;
import javax.microedition.midlet.MIDletStateChangeException;/** @author sodino */
public class Base64Test extends MIDlet { protected void destroyApp(boolean unconditional) throws MIDletStateChangeException { } protected void pauseApp() { } protected void startApp() throws MIDletStateChangeException {
Display.getDisplay(this).setCurrent(new MyCanvas());
} private class MyCanvas extends Canvas {
private Image instanceImg; public MyCanvas() {
//创建原始图片
Image originalImg = createInstanceImg();
//获取图片int数据数组
int[] data = new int[originalImg.getWidth() * originalImg.getHeight()];
originalImg.getRGB(data, 0, originalImg.getWidth(), 0, 0, originalImg.getWidth(), originalImg.getHeight());
//转化为byte数组
byte[] byteData = convertIntToByte(data);
//Base64 encode
String baseEncode = Base64.encode(byteData);
//Base64 decode
byte[] byteArr = Base64.decode(baseEncode);
//恢复图片数据
int[] dataArr = convertByteToInt(byteArr);
//恢复图片
instanceImg = Image.createRGBImage(dataArr, originalImg.getWidth(), originalImg.getHeight(), true);
} private byte[] convertIntToByte(int[] data) {
if (data == null) {
return null;
}
byte[] byteArr = new byte[data.length << 2];
for (int i = 0; i < data.length; i++) {
int num = data[i];
byteArr[i * 4 + 0] = (byte) (num >>> 0);
byteArr[i * 4 + 1] = (byte) (num >>> 8);
byteArr[i * 4 + 2] = (byte) (num >>> 16);
byteArr[i * 4 + 3] = (byte) (num >>> 24);
}
return byteArr;
} private int[] convertByteToInt(byte[] byteArr) {
if (byteArr == null || byteArr.length == 0 || byteArr.length % 4 != 0) {
return null;
}
int[] data = new int[byteArr.length >> 2];
for (int i = 0; i < data.length; i++) {
data[i] = ((int) (byteArr[i * 4 + 0] << 0)) | ((int) (byteArr[i * 4 + 1] << 8))
| ((int) (byteArr[i * 4 + 2] << 16)) | ((int) (byteArr[i * 4 + 3] << 24));
}
return data;
} private Image createInstanceImg() {
int length = 200;
int padding = 30;
Image img = Image.createImage(length, length);
Graphics g = img.getGraphics();
g.setColor(0xff0000);
g.fillRect(0, 0, length, length);
g.setColor(0xffff00);
g.drawString("Base64Test", length >> 1, length >> 1, Graphics.HCENTER | Graphics.TOP);
g.drawString("Base64Test", length >> 1, length >> 1 + padding, Graphics.HCENTER | Graphics.TOP);
return img;
} protected void paint(Graphics g) {
g.setColor(0xffffff);
g.fillRect(0, 0, 240, 320);
g.drawImage(instanceImg, 0, 0, 0);
} }
}
package lab.sodino.base64;import java.io.ByteArrayOutputStream;/**
* base64 format encoding & decoding
*/
public class Base64 { private static char[] base64EncodeChars = new char[] { 'A', 'B', 'C', 'D', 'E', 'F', 'G', 'H', 'I', 'J', 'K', 'L',
'M', 'N', 'O', 'P', 'Q', 'R', 'S', 'T', 'U', 'V', 'W', 'X', 'Y', 'Z', 'a', 'b', 'c', 'd', 'e', 'f', 'g',
'h', 'i', 'j', 'k', 'l', 'm', 'n', 'o', 'p', 'q', 'r', 's', 't', 'u', 'v', 'w', 'x', 'y', 'z', '0', '1',
'2', '3', '4', '5', '6', '7', '8', '9', '+', '/' };
private static byte[] base64DecodeChars = new byte[] { -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1,
-1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1,
-1, 62, -1, -1, -1, 63, 52, 53, 54, 55, 56, 57, 58, 59, 60, 61, -1, -1, -1, -1, -1, -1, -1, 0, 1, 2, 3, 4,
5, 6, 7, 8, 9, 10, 11, 12, 13, 14, 15, 16, 17, 18, 19, 20, 21, 22, 23, 24, 25, -1, -1, -1, -1, -1, -1, 26,
27, 28, 29, 30, 31, 32, 33, 34, 35, 36, 37, 38, 39, 40, 41, 42, 43, 44, 45, 46, 47, 48, 49, 50, 51, -1, -1,
-1, -1, -1 }; private Base64() {
} public static String encode(byte[] data) {
StringBuffer sb = new StringBuffer();
int len = data.length;
int i = 0;
int b1, b2, b3; while (i < len) {
b1 = data[i++] & 0xff;
if (i == len) {
sb.append(base64EncodeChars[b1 >>> 2]);
sb.append(base64EncodeChars[(b1 & 0x3) << 4]);
sb.append("==");
break;
}
b2 = data[i++] & 0xff;
if (i == len) {
sb.append(base64EncodeChars[b1 >>> 2]);
sb.append(base64EncodeChars[((b1 & 0x03) << 4) | ((b2 & 0xf0) >>> 4)]);
sb.append(base64EncodeChars[(b2 & 0x0f) << 2]);
sb.append("=");
break;
}
b3 = data[i++] & 0xff;
sb.append(base64EncodeChars[b1 >>> 2]);
sb.append(base64EncodeChars[((b1 & 0x03) << 4) | ((b2 & 0xf0) >>> 4)]);
sb.append(base64EncodeChars[((b2 & 0x0f) << 2) | ((b3 & 0xc0) >>> 6)]);
sb.append(base64EncodeChars[b3 & 0x3f]);
}
return sb.toString();
} public static byte[] decode(String str) {
byte[] data = str.getBytes();
int len = data.length;
ByteArrayOutputStream buf = new ByteArrayOutputStream(len);
int i = 0;
int b1, b2, b3, b4; while (i < len) { /* b1 */
do {
b1 = base64DecodeChars[data[i++]];
} while (i < len && b1 == -1);
if (b1 == -1) {
break;
} /* b2 */
do {
b2 = base64DecodeChars[data[i++]];
} while (i < len && b2 == -1);
if (b2 == -1) {
break;
}
buf.write((int) ((b1 << 2) | ((b2 & 0x30) >>> 4))); /* b3 */
do {
b3 = data[i++];
if (b3 == 61) {
return buf.toByteArray();
}
b3 = base64DecodeChars[b3];
} while (i < len && b3 == -1);
if (b3 == -1) {
break;
}
buf.write((int) (((b2 & 0x0f) << 4) | ((b3 & 0x3c) >>> 2))); /* b4 */
do {
b4 = data[i++];
if (b4 == 61) {
return buf.toByteArray();
}
b4 = base64DecodeChars[b4];
} while (i < len && b4 == -1);
if (b4 == -1) {
break;
}
buf.write((int) (((b3 & 0x03) << 6) | b4));
}
return buf.toByteArray();
}
}
粗糙地写了一下,看下是不是楼主想要的
晕,那你发j2me区来干嘛!!
org.apache.commons.codec.binary.Base64
lz自己看下。