在iReport中计算SHA1或MD5哈希

本文介绍了在iReport中计算SHA1或MD5哈希的处理方法，对大家解决问题具有一定的参考价值，需要的朋友们下面随着小编来一起学习吧！ 问题描述

在执行报告时，如何在iReport中计算SHA1或MD5哈希?我需要将预先计算的哈希与数据库驱动的字段(字符串)进行比较.

How would one calculate an SHA1 or MD5 hash within iReport at report execution? I need to compare a pre-calculated hash against a database driven field (string).

使用iReport 2.0.5(旧版)，并将Report Engine嵌入到商业应用程序中.

Using iReport 2.0.5 (Old) and Report Engine is embedded into a commercial application.

推荐答案

几年前，我使用了iReport和Jasper Reports，但我不记得详细信息，但我记得您可以通过某种方式放置要评估的Java代码. .使用该功能，您可以在几行中计算MD5:

I used iReport and Jasper Reports some years ago and I don't remember the details, but I remember that you could put in some way Java code to be evaluated. Using that feature you could calculate the MD5 in few lines:

String encryptionAlgorithm = "MD5"; String valueToEncrypt = "StackOverflow"; MessageDigest msgDgst = MessageDigest.getInstance(encryptionAlgorithm); msgDgst.update(valueToEncrypt.getBytes(), 0, valueToEncrypt.length()); String md5 = new BigInteger(1, msgDgst.digest()).toString(16) ; System.out.println(md5);

需要导入java.math.BigInteger，java.security.MessageDigest和java.security.NoSuchAlgorithmException;

Need to import java.math.BigInteger, java.security.MessageDigest and java.security.NoSuchAlgorithmException;

要计算SHA1哈希值几乎是相同的:

To calculate SHA1 hash is almost the same:

String encryptionAlgorithm = "SHA-1"; String valueToEncrypt = "StackOverflow"; MessageDigest msgDgst = MessageDigest.getInstance(encryptionAlgorithm); byte[] sha1hash = new byte[40]; msgDgst.update(valueToEncrypt.getBytes(), 0, valueToEncrypt.length()); sha1hash = md.digest();

查看此博客文章，了解可以在报表运行时评估的变量 www.eakes/77/java-injection-in-jasper-reports/

Check this blog post about the creation of variables that can be evaluated at report run time www.eakes/77/java-injection-in-jasper-reports/