Javac 声称采用 Character[][] 的方法在泛型类中不存在

Question

我收到编译错误，但我不明白为什么。

控制台输出:

[javac] Compiling 43 source files to C:\Users\Janus\Desktop\gdi1_projekt\gwittest\build\classes
[javac] C:\Users\Janus\Desktop\gdi1_projekt\gwittest\src\testpackage\shared\ship\exceptions\InvalidLevelException.java:43: cannot find symbol
[javac] symbol  : method getBoardString(java.lang.Character[][])
[javac] location: class testpackage.shared.ship.Map2DHelper<java.lang.Character>
[javac]                     System.err.println(helper.getBoardString(char3d[0]));
[javac]                                              ^
[javac] C:\Users\Janus\Desktop\gdi1_projekt\gwittest\src\testpackage\shared\ship\exceptions\InvalidLevelException.java:45: cannot find symbol
[javac] symbol  : method getBoardString(java.lang.Character[][])
[javac] location: class testpackage.shared.ship.Map2DHelper<java.lang.Character>
[javac]                     System.err.println(helper.getBoardString(char3d[1]));
[javac]                                              ^
[javac] Note: Some input files use unchecked or unsafe operations.
[javac] Note: Recompile with -Xlint:unchecked for details.
[javac] 2 errors

BUILD FAILED

无效级别异常:

package testpackage.shared.ship.exceptions;

import java.util.List;

import testpackage.shared.ship.Map2DHelper;

public class InvalidLevelException extends RuntimeException {
    private String message; 
    private List<List<Character>> list2d;
    private Character[][][] char3d;
    private BoardType type;

    private enum BoardType {
            Char3D, List2D
    }

    public InvalidLevelException(String string) {
            this.message = string;
    }
    public void setBoards(Character[][][] char3d) {
            this.type = BoardType.Char3D;
            this.char3d = char3d;
    }
    public InvalidLevelException(String string, Character[][][] char3d) {
            this(string);
            this.type = BoardType.Char3D;
            this.char3d = char3d;
    }
    public InvalidLevelException(String string, List<List<Character>> list2d) {
            this(string);
            this.type = BoardType.List2D;
            this.list2d = list2d;
    }
    public String getMessage() {
            return message + (type == null ? "" : ". Invalid board available. Call InvalidLevelException.printBoard()");
    }
    public void printBoard() {
            if (type == null) {
                    System.err.println("No invalid board available for debugging.");
            } else if (type == BoardType.Char3D) {
                    Map2DHelper<Character> helper = new Map2DHelper<Character>();
                    System.err.println(helper.getBoardString(char3d[0]));
                    System.err.println();
                    System.err.println(helper.getBoardString(char3d[1]));
            } else if (type == BoardType.List2D) {
                    Map2DHelper<Character> helper = new Map2DHelper<Character>();
                    System.err.println(helper.getBoardString(list2d));
            } else {
                    System.err.println("Don't know how to print invalid board.");
            }
    }

    private static final long serialVersionUID = 1L;
}

Map2DHelper 片段:

public class Map2DHelper<T> {
public String getBoardString(List<List<T>> a) {
    StringBuilder sb = new StringBuilder();
    for (int i = 0; i < a.size(); i++) {
        for (int j = 0; j < a.get(i).size(); j++) {
            //sb.append(Integer.toString(i) + "," + Integer.toString(j));
            sb.append(Util.format("%d ", a.get(i).get(j)));
        }
        sb.append("\n");
    }
    sb.append("\n");
    return sb.toString();
}


String getBoardString(T[][] a) {
    StringBuilder sb = new StringBuilder();
    for (int i = 0; i < a.length; i++) {
        for (int j = 0; j < a[i].length; j++) {
            //System.err.println(a[i][j]);
            sb.append(String.format("%d ", a[i][j]));
        }
        sb.append("\n");
    }
    sb.append("\n");
    //System.err.println(sb.toString());
    return sb.toString();
}
}

构建脚本(我使用默认的清理目标):

<project name="HelloWorld" basedir="." default="main">
    <property name="gwt.user" value="jars/gwt-2.3.0/gwt-user.jar" />
    <property name="translator" value="jars/translator.jar"/>
    <property name="acm" value="jars/acm.jar"/>
    <path id="project.class.path">
       <pathelement path="jars/mp3spi1.9.5.jar" />
       <pathelement path="jars/tritonus_share.jar" />
       <pathelement path="jars/commons-io-2.0.1.jar" />
       <pathelement path="jars/jl1.0.1.jar" />
       <pathelement path="jars/junit-4.9b3.jar"/>
       <pathelement path="${gwt.user}" />
       <pathelement path="${acm}" />
       <pathelement path="${translator}" />
    </path>

    <property name="src.dir"     value="src"/>

    <property name="build.dir"   value="build"/>
    <property name="classes.dir" value="${build.dir}/classes"/>
    <property name="jar.dir"     value="${build.dir}/jar"/>

    <property name="main-class"  value="testpackage.interfaces.GUISchiffe" />

    <target name="clean">
        <delete dir="${build.dir}"/>
    </target>

    <target name="compile">
        <mkdir dir="${classes.dir}"/>
        <javac srcdir="${src.dir}" destdir="${classes.dir}" debug="on" debuglevel="lines,vars,source">
      <exclude name="testpackage/highscore/*.java" />
          <classpath refid="project.class.path" />
        </javac>

    </target>

    <target name="jar" depends="compile">
        <mkdir dir="${jar.dir}"/>
        <manifestclasspath property="jar-class-path" jarfile="${jar.dir}/${ant.project.name}.jar">
          <classpath refid="project.class.path"/>
        </manifestclasspath>

        <jar destfile="${jar.dir}/${ant.project.name}.jar" basedir="${classes.dir}">
            <manifest>
                <attribute name="Main-Class" value="${main-class}" />
        <attribute name="Class-Path" value="${jar-class-path}" />
            </manifest>
        <fileset dir="war/template"/>
        </jar>
    </target>

    <target name="run" depends="jar">
        <java jar="${jar.dir}/${ant.project.name}.jar" classpathref="project.class.path" fork="true" />
    </target>

    <target name="alternaterun" depends="jar">
       <java classname="testpackage.interfaces.SoundStreamPlayer">
         <classpath>
           <pathelement location="${jar.dir}/${ant.project.name}.jar" />
           <path refid="project.class.path" />
         </classpath>
       </java>

    </target>

    <target name="linux-run" depends="jar">
    <exec executable="/usr/bin/aoss">
        <arg value="/usr/lib/jvm/java-6-sun/bin/java" />
        <arg value="-jar" />
        <arg value="build/jar/HelloWorld.jar" />
    </exec>
    </target>

    <target name="clean-build" depends="clean,jar"/>

    <target name="main" depends="clean,run"/>

</project>

Answer 1

是否只是 getBoardString(T[][] ... 不是公开的？由于您在第一次欲望开始时导入该类，我想它们不在同一个包中。