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Upgrade From Jdk6 to Jdk17

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Upgrade From Jdk6 to Jdk17

From Jdk6 to Jdk17

若有錯誤, 請修正後分享。

Customizing Maven Clean Plugin for target Directory

如果有用同步程式, 可能會先設定target目錄不要同步。
但是mvn clean預設會刪除再重新建立target目錄, 導致不要同步的旗標會消失。
下方設定, 能避免mvn clean刪除target目錄。

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<build>
    <plugins>
        <plugin>
            <groupId>org.apache.maven.plugins</groupId>
            <artifactId>maven-clean-plugin</artifactId>
            <version>3.3.2</version>
            <executions>
                <execution>
                    <id>Deleting all files under target, but not target itself</id>
                    <phase>clean</phase>
                    <goals>
                        <goal>clean</goal>
                    </goals>
                </execution>
            </executions>
            <configuration>
                <excludeDefaultDirectories>true</excludeDefaultDirectories>
                <filesets>
                    <fileset>
                        <directory>target/</directory>
                        <followSymlinks>false</followSymlinks>
                        <includes>
                            <include>**/*</include>
                        </includes>
                    </fileset>
                </filesets>
            </configuration>
        </plugin>
    </plugins>
</build>

Using JARs from Others Directly

有時會想直接想用別人的 jar 檔,
這個 plugin 可以用mvn clean就用lib目錄裡的檔案自動更新本機 mvn repository 的檔案:

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<plugin>
   <groupId>org.apache.maven.plugins</groupId>
   <artifactId>maven-install-plugin</artifactId>
   <version>2.5.2</version>
   <executions>
      <execution>
      <id>install_org_story</id>
      <phase>clean</phase>
          <goals>
              <goal>install-file</goal>
          </goals>
          <configuration>
             <groupId>org.story</groupId>
             <artifactId>story</artifactId>
             <version>1.0</version>
             <packaging>jar</packaging>
             <file>${basedir}/lib/Some.jar</file>
          </configuration>
      </execution>
   </executions>
</plugin>

Codebase Compatibility

Unsupported Java 6 APIs.

e.g. sun.misc packages

encoder

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String encodedBytes = new sun.misc.BASE64Encoder().encode("exampleString")

改成:

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String encodedBytes = Base64.getMimeEncoder().encodeToString("exampleString")

decoder

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byte[] decodedBytes = new sun.misc.BASE64Decoder().decodeBuffer("exampleString")

改成:

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byte[] decodedBytes = Base64.getMimeDecoder().decode("exampleString");

Tomcat10 Handles UTF-8 Encoding by Default

不要再轉成ISO-8859-1:

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transNo = request.getParameter("TRANSNO");
transNo = new String(transNo.getBytes("ISO-8859-1"), "UTF-8");

Date and Time Handling

Legacy Code Using Joda-Time

Joda 官網也是寫要改用 Java8 內建的時間API。

Note that from Java SE 8 onwards, users are asked to migrate to java.time (JSR-310) - a core part of the JDK which replaces this project. – www.joda.org

但是 Java8 之後還是沒有 JodaTime 的 Interval, 可以考慮使用 threeten-extra 的 Interval.

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<dependency>
  <groupId>org.threeten</groupId>
  <artifactId>threeten-extra</artifactId>
  <version>1.8.0</version>
</dependency>

DisplayTag Compatibility

web.xml 裡的 display filter 移除

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<filter-class>org.displaytag.filter.ResponseOverrideFilter</filter-class>

java.awt.Font

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Font font=new Font("字型",Font.TRUETYPE_FONT, 12);

改成建立後再指定字型大小

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InputStream fontStream = getClass().getResourceAsStream("/edukai-5.0.ttf");
Font font = Font.createFont(Font.TRUETYPE_FONT, fontStream).deriveFont(12f);

POI

儲存格

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cellStyle.setBorderTop(CellStyle.BORDER_THIN);
cellStyle.setBorderRight(CellStyle.BORDER_THIN);
cellStyle.setBorderBottom(CellStyle.BORDER_THIN);
cellStyle.setBorderLeft(CellStyle.BORDER_THIN);
cellStyle.setAlignment(HSSFCellStyle.ALIGN_CENTER);
cellStyle.setVerticalAlignment(HSSFCellStyle.VERTICAL_CENTER);

改成:

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cellStyle.setBorderTop(BorderStyle.THIN);
cellStyle.setBorderRight(BorderStyle.THIN);
cellStyle.setBorderBottom(BorderStyle.THIN);
cellStyle.setBorderLeft(BorderStyle.THIN);
cellStyle.setAlignment(HorizontalAlignment.CENTER);
cellStyle.setVerticalAlignment(VerticalAlignment.CENTER);

字型相關

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font.setColor(HSSFColor.BLACK.index);
font.setBoldweight(Font.BOLDWEIGHT_BOLD);

改成:

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font.setColor(HSSFColor.HSSFColorPredefined.BLACK.getIndex());
font.setBold(true);

Legacy Documents Resolved a Testing Discrepancy

最好還是要有原本的設計文件,
業務單位測試以為匯出的報表會有日期欄位,
但是查看程式, 真的就特地略過日期欄位。
還好他手邊有之前印過的, 才想起來是那個功能很特別, 就是不會有日期欄位, 是隔壁的按鈕才會有。

(Optional) Using Git for Project Organization

git-svn

因為不想在本機分不同目錄儲存 Jdk6, Jdk17 版本,
所以請教周組長後, 試著用git-svn來操作。 但是目前懂的不多,
無法提供協助, 請斟酌使用。

  1. Clone from svn
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    git svn init https://svn-server/svn/personnel_matters --trunk=PrivLib --branches=MavenizeProjects/{PrivLib} PrivLib
  2. Setting the authorsfile
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git config svn.authorsfile ~/authors.txt
  1. Edit content of .git/config:
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[core]
    repositoryformatversion = 0
    filemode = true
    bare = false  
    logallrefupdates = true
    ignorecase = true
    precomposeunicode = true
[svn-remote "svn"]
    url = https://svn-server/svn/personnel_matters
    fetch = PrivLib:refs/remotes/origin/trunk
    branches = MavenizeProjects/{PrivLib}/*:refs/remotes/origin/*
[svn]
    authorsfile = ~/authors_PmbMgr.txt

Modify these line:

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fetch = PrivLib:refs/remotes/origin/trunk
branches = MavenizeProjects/{PrivLib}/*:refs/remotes/origin/*

to

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fetch = PrivLib:refs/remotes/git-svn/trunk
branches = MavenizeProjects/{PrivLib}:refs/remotes/feature-jdk17/*
  1. fetch
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git svn fetch

might need to expand log size:

git svn fetch --log-window-size=6500
  1. checkout feature-jdk17/PrivLib
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Note: switching to 'feature-jdk17/PrivLib'.

You are in 'detached HEAD' state. You can look around, make experimental
changes and commit them, and you can discard any commits you make in this
state without impacting any branches by switching back to a branch.

If you want to create a new branch to retain commits you create, you may
do so (now or later) by using -c with the switch command. Example:

  git switch -c <new-branch-name>

Or undo this operation with:

  git switch -

Turn off this advice by setting config variable advice.detachedHead to false

HEAD is now at 08b92ec jdk17版: 已同步原 jdk6 的 r5161
➜  ~/Downloads/PrivLib git:(08b92ec) git branch
➜  ~/Downloads/PrivLib git:(08b92ec)
  1. switch -c
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git switch -c feature-jdk17
  1. 合併 不可以在master直接merge或rebase feature-jdk17 !
    會導致master的svnmetadata 被覆蓋。
    目前只會用cherry-pick的非正規方式合併。
    如果有找到方法, 觀迎分享。
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git cherry-pick master..feature-jdk17
git
git
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