编辑代码

import java.io.ByteArrayInputStream;

import java.io.ByteArrayOutputStream;

import java.io.InputStream;

import java.security.KeyFactory;

import java.security.PrivateKey;

import java.security.PublicKey;

import java.security.spec.PKCS8EncodedKeySpec;

import java.security.spec.X509EncodedKeySpec;

import javax.crypto.Cipher;
import java.util.Base64;

class Main {
	public static void main(String[] args) {
		System.out.println(sign("1042819028#051042819028#05"));
        //W3siYW1vdW50IjoiIiwib3JkZXJObyI6IjIwMjMwMTAyMTQyMDIxMTAxODMzMjg3MCIsInN1Ym1lck5hbWUiOiLljY7mtqbnh4PmsJQiLCJnb29kc1Jlc3MiOiLljY7mtqbnh4PmsJQiLCJzdWJtZXJDb2RlIjoiMDAxIiwicmVtYXJrIjoie29yZ05vOldDUlEwLGJyYWNoQ29kZTpudWxsLGNvbnNObzoxMDQyODE5MDI4LGFjY3RObzoxMDAwMDAzNjA2OTQ3NDE2LGNoZWNrSWQ6QjI0NldDUlEwMjAyMzAxMDIsfSIsIml0ZW1zIjpbeyJnb29kc05hbWUiOiLnh4PmsJTotLnnlKgiLCJnb29kc1R5cGUiOiLnh4PmsJTotLnnlKgifV19XQ==
	}


	public static String sign(String content)

	{
		String privateKey = "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";

		try

		{
			PKCS8EncodedKeySpec priPKCS8 = new PKCS8EncodedKeySpec(Base64.getDecoder().decode(privateKey));

			KeyFactory keyf = KeyFactory.getInstance("RSA");

			PrivateKey priKey = keyf.generatePrivate(priPKCS8);

			java.security.Signature signature = java.security.Signature.getInstance("SHA1withRSA");

			signature.initSign(priKey);

			signature.update(content.getBytes("UTF-8"));

			byte[] signed = signature.sign();

			return Base64.getEncoder().encodeToString(signed);

		}

		catch(Exception e)

		{

			e.printStackTrace();

		}

		return null;

	}

}