Java 在ant/netbeans中定义init之前的常量

我有一个要在Tomcat6/JbossAS 5上运行的webapp，出于版本控制的目的，我有几个和目标，它们将执行一组操作来定义一个带有版本号和构建日期时间的常量

目标执行以下操作：

<target name="build-config" >
    <!-- config -->
    <property name="project.name" value="MY PROJECT" />
    <property name="release.prefix" value="MPROJECT" />
    <property name="release.num" value="1.0" />
    <property name="release.info.file.path" value="org/my/project/Release" />
    <tstamp>
        <format property="release.date" pattern="yyyy-MM-dd HH:mm:ss z" />
    </tstamp>
    <!-- end config -->
    <property name="release.version" value="${release.prefix}-${release.num}" />
    <property name="release.info" value="${release.version} ${release.date}" />
</target>
<target name="build-replace">
    <filter token="release.info" value="${release.version} ${release.date}" />
    <delete file="${src.dir}/${release.info.file.path}.java" />
    <copy file="${src.dir}/${release.info.file.path}.template" tofile="${src.dir}/${release.info.file.path}.java" filtering="true" />
</target>

<target name="build-myproj-1.0.jar" depends="init,buil-config,build-replace,compile">
    <mkdir dir="${dist.dir}"/>
    <jar compress="true" jarfile="${dist.dir}/MPROJECT-1.0.jar">
        <fileset dir="${build.classes.dir}"
               excludes="META-INF/*.*, WEB-INF/classes/*.xml"
               includes="**/*.class"
        />
        <manifest>
            <section name="${project.name}">
                <attribute name="Release-Version" value="${release.version}" />
                <attribute name="Release-Date" value="${release.date}" />
            </section>
        </manifest>
    </jar>
</target>

删除Release.java

将Release.template复制到Release.java，并将版本控制信息正确设置为常量（公共静态最终字符串）

问题是，在编译之前，代码上的常量引用会被替换。比如说，我在哪里

log.debug("Release: " + Release.info);

使用java反编译器，我可以看到以下内容（假设“TO_BE__DEFINED”是Relase.info的初始值）：

目标如下：

<target name="build-config" >
    <!-- config -->
    <property name="project.name" value="MY PROJECT" />
    <property name="release.prefix" value="MPROJECT" />
    <property name="release.num" value="1.0" />
    <property name="release.info.file.path" value="org/my/project/Release" />
    <tstamp>
        <format property="release.date" pattern="yyyy-MM-dd HH:mm:ss z" />
    </tstamp>
    <!-- end config -->
    <property name="release.version" value="${release.prefix}-${release.num}" />
    <property name="release.info" value="${release.version} ${release.date}" />
</target>
<target name="build-replace">
    <filter token="release.info" value="${release.version} ${release.date}" />
    <delete file="${src.dir}/${release.info.file.path}.java" />
    <copy file="${src.dir}/${release.info.file.path}.template" tofile="${src.dir}/${release.info.file.path}.java" filtering="true" />
</target>

<target name="build-myproj-1.0.jar" depends="init,buil-config,build-replace,compile">
    <mkdir dir="${dist.dir}"/>
    <jar compress="true" jarfile="${dist.dir}/MPROJECT-1.0.jar">
        <fileset dir="${build.classes.dir}"
               excludes="META-INF/*.*, WEB-INF/classes/*.xml"
               includes="**/*.class"
        />
        <manifest>
            <section name="${project.name}">
                <attribute name="Release-Version" value="${release.version}" />
                <attribute name="Release-Date" value="${release.date}" />
            </section>
        </manifest>
    </jar>
</target>

---

我知道这可能有点让人困惑，如果我遗漏了一些信息，请随时询问

在编译客户机代码时，是否在客户机代码中替换编译时常量

要让客户机代码获取常量的新值，可以重新编译所有内容，用getter替换字段，或者使用

public abstract class Release {

/** Release info */
public static final String INFO = "TO_BE_DEFINED";
}