js加密: 用FileReader中的readAsDataURL(file)即可, 但注意, 得到的字符串中, 第一个(也是唯一一个),之前保存的是文件类型和加密类型, 之后保存的才是加密后的字符串

• FileReader: The FileReader object lets web applications asynchronously read the contents of files (or raw data buffers) stored on the user's computer, using File or Blob objects to specify the file or data to read.
  • 异步方法的处理: 当FileReader触发了一些事件后, 会返回相应的数据:
    • onload: 加载完成时触发, 会返回结果
    • onerror: 读取操作发生错误时触发
    • 等等
• 例子:

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  var reader = new FileReader(); reader.readAsDataURL(fileObj); reader.onload = function () { var encodeString = reader.result; console.log(encodeString); customFormField1.fieldName = "customFormField1Name"; customFormField1.fieldValue = "customFormField1Value"; customFormField0.fieldName = "customFormField0Name"; customFormField0.fieldValue = "customFormField0Value"; customFormFileField0.name = "customFormFileField0Name"; customFormFileField0.encodedContent = encodeString; customFormFileField0.postfix = "docx"; customFormFields[0] = customFormField0; customFormFields[1] = customFormField1; customFiles[0] = customFormFileField0; customForm.customFormFields = customFormFields; customForm.type = 0; customForm.senderId = 19; request.customForm = customForm; request.customFiles = customFiles; request.integer = 7; request.string = "秘书长"; request = JSON.stringify(request); $.ajax({ type: "POST", url: "http://192.168.0.113:8090/form/addForm.jspx", data: request, dataType: "json", contentType: "application/json", cache: false, processData: false, success: function (data) { console.log("success: " + data); }, error: function (data) { console.log("fail: " + data); } }); }

java

• 加密:
  • 先使用NIO中的Files.readAllBytes读取文件为byte[]
  • 再用java.util中的Base64.getEncoder().encodeToString()加密
• 解密:
  • 如果加密的string中包含文件类型和加密类型信息, 先截取掉
  • 利用Base64.getDecoder().decode将String解密成byte[]
  • 利用Files.write将byte[]写入指定位置

• Files.readAllBytes(): 根据路径读取所有byte, 实现中用到大量Channel
• Files.write(): 向给定路径写入给定byte, StandardOpenOption defines the standard open options

详见:

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Project Coin provides numerous "small language enhancements" as a subset of the new JDK 7 features. I recently blogged on Project Coin's switching on Strings and in this post I write about the new Diamond Operator (<>).

The Diamond Operator reduces some of Java's verbosity surrounding generics by having the compiler infer parameter types for constructors of generic classes. The original proposal for adding the Diamond Operator to the Java language was made in February 2009 and includes this simple example:

For example, consider the following assignment statement:

Map<String, List<String>> anagrams = new HashMap<String, List<String>>();

This is rather lengthy, so it can be replaced with this:

Map<String, List<String>> anagrams = new HashMap<>();

The above example provided in Jeremy Manson's proposal (which was one of the first in response to a call for Project Coin ideas) is simple, but adequately demonstrates how the Diamond Operator is applied in JDK 7. Manson's proposal also provides significant into why this addition was desirable:

The requirement that type parameters be duplicated unnecessarily like

this encourages an unfortunate

overabundance of static factory methods, simply because type inference

works on method invocations.

In other words, the JDK 7 Project Coin addition of a Diamond Operator brings type inference to constructors that has been available with methods. With methods type inference is implicitly done when one leaves off the explicit parameter type specification. With instantiation, on the other hand, the diamond operator must be specified explicitly to "tell" the compiler to infer the type.

参考文档: https://www.javaworld.com/article/2074080/core-java/jdk-7--the-diamond-operator.html

例:

例子:

• result set:

  1 2 3 4 5

  Columns: id, gmt_create, gmt_modify, is_active, sender_id, receiver_id, type, is_agreed, process_url, process_reason, id, gmt_create, gmt_modify, is_active, form_id, field_name, field_value Row: 1, 2018-04-18 18:58:06.0, 2018-04-18 18:58:06.0, 1, 19, 18, 0, null, null, null, 1, 2018-04-18 19:01:52.0, 2018-04-18 19:05:15.0, 1, 1, name, 德玛西亚 Row: 1, 2018-04-18 18:58:06.0, 2018-04-18 18:58:06.0, 1, 19, 18, 0, null, null, null, 2, 2018-04-18 19:02:04.0, 2018-04-18 19:05:02.0, 1, 1, gender, 男 Row: 1, 2018-04-18 18:58:06.0, 2018-04-18 18:58:06.0, 1, 19, 18, 0, null, null, null, 3, 2018-04-18 19:02:10.0, 2018-04-18 19:04:58.0, 1, 1, nation, 中国 Row: 1, 2018-04-18 18:58:06.0, 2018-04-18 18:58:06.0, 1, 19, 18, 0, null, null, null, 4, 2018-04-18 19:02:16.0, 2018-04-18 19:04:54.0, 1, 1, birth, 19910526

• 转换后的json:

1. 为数据库操作序列提供了一个从失败中恢复到正常状态的方法, 同时提供了数据库即使在异常状态下仍能保持一致性的方法
2. 当多个应用程序在并发访问数据库时, 可以在这些应用程序之间提供一个隔离方法, 以防止彼此的操作互相干扰

• 原子性(Atomicity): 事务作为一个整体被执行, 包含在其中的对数据库的操作要么全部被执行, 要么都不执行
• 一致性(Consistency): 事务应确保数据库的状态从一个一致状态转变为另一个一致状态. 一致状态的含义是数据库中的数据应满足完整性约束
• 隔离性(Isolation): 多个事务并发执行时, 一个事务的执行不应该影响其他事务的执行
• 持久性(Durability): 已被提交的事务对数据库的修改应该永久保存在数据库中