Java Tree用于表示路径列表中的文件系统(files/dir)

Question

我有这样的路径列表

/mnt/sdcard/folder1/a/b/file1
/mnt/sdcard/folder1/a/b/file2
/mnt/sdcard/folder1/a/b/file3
/mnt/sdcard/folder1/a/b/file4
/mnt/sdcard/folder1/a/b/file5
/mnt/sdcard/folder1/e/c/file6
/mnt/sdcard/folder2/d/file7
/mnt/sdcard/folder2/d/file8
/mnt/sdcard/file9

因此,从这个路径列表(Stings)我需要创建一个Java Tree结构,其中包含文件夹作为节点,文件作为leaf(不会将空文件夹作为叶子).

我需要的是我想的是add方法,我向它们传递一个String(文件的路径),然后将它添加到树中的正确位置,如果它们不在那里,则创建正确的节点(Folder)

当我在节点和叶子列表上时,这个树结构将需要我获取节点列表(但我认为这将是树的常规功能)

我总是将字符串作为路径而不是真正的文件或文件夹.是否有可以使用的东西或源代码开始？

非常感谢你.

Answer 1

谢谢你的所有答案.我做了我的工作实施.我认为我需要对其进行改进,以便在向树结构添加元素时使用更多缓存来使其更好地工作.

正如我所说的,我需要的是一种允许我对FS进行"虚拟"描述的结构.

MXMTree.java

public class MXMTree {

    MXMNode root;
    MXMNode commonRoot;

    public MXMTree( MXMNode root ) {
        this.root = root;
        commonRoot = null;
    }

    public void addElement( String elementValue ) { 
        String[] list = elementValue.split("/");

        // latest element of the list is the filename.extrension
        root.addElement(root.incrementalPath, list);

    }

    public void printTree() {
        //I move the tree common root to the current common root because I don't mind about initial folder
        //that has only 1 child (and no leaf)
        getCommonRoot();
        commonRoot.printNode(0);
    }

    public MXMNode getCommonRoot() {
        if ( commonRoot != null)
            return commonRoot;
        else {
            MXMNode current = root;
            while ( current.leafs.size() <= 0 ) {
                current = current.childs.get(0);
            }
            commonRoot = current;
            return commonRoot;
        }

    }


}

MXMNode.java

import java.util.ArrayList;
import java.util.Arrays;
import java.util.List;


public class MXMNode {

    List<MXMNode> childs;
    List<MXMNode> leafs;
    String data;
    String incrementalPath;

    public MXMNode( String nodeValue, String incrementalPath ) {
        childs = new ArrayList<MXMNode>();
        leafs = new ArrayList<MXMNode>();
        data = nodeValue;
        this. incrementalPath = incrementalPath;
    }

    public boolean isLeaf() {
        return childs.isEmpty() && leafs.isEmpty();
    }

    public void addElement(String currentPath, String[] list) {

        //Avoid first element that can be an empty string if you split a string that has a starting slash as /sd/card/
        while( list[0] == null || list[0].equals("") )
            list = Arrays.copyOfRange(list, 1, list.length);

        MXMNode currentChild = new MXMNode(list[0], currentPath+"/"+list[0]);
        if ( list.length == 1 ) {
            leafs.add( currentChild );
            return;
        } else {
            int index = childs.indexOf( currentChild );
            if ( index == -1 ) {
                childs.add( currentChild );
                currentChild.addElement(currentChild.incrementalPath, Arrays.copyOfRange(list, 1, list.length));
            } else {
                MXMNode nextChild = childs.get(index);
                nextChild.addElement(currentChild.incrementalPath, Arrays.copyOfRange(list, 1, list.length));
            }
        }
    }

    @Override
    public boolean equals(Object obj) {
        MXMNode cmpObj = (MXMNode)obj;
        return incrementalPath.equals( cmpObj.incrementalPath ) && data.equals( cmpObj.data );
    }

    public void printNode( int increment ) {
        for (int i = 0; i < increment; i++) {
            System.out.print(" ");
        }
        System.out.println(incrementalPath + (isLeaf() ? " -> " + data : "")  );
        for( MXMNode n: childs)
            n.printNode(increment+2);
        for( MXMNode n: leafs)
            n.printNode(increment+2);
    }

    @Override
    public String toString() {
        return data;
    }


}

Test.java用于测试代码

public class Test {

    /**
     * @param args
     */
    public static void main(String[] args) {

        String slist[] = new String[] { 
                "/mnt/sdcard/folder1/a/b/file1.file", 
                "/mnt/sdcard/folder1/a/b/file2.file", 
                "/mnt/sdcard/folder1/a/b/file3.file", 
                "/mnt/sdcard/folder1/a/b/file4.file",
                "/mnt/sdcard/folder1/a/b/file5.file", 
                "/mnt/sdcard/folder1/e/c/file6.file", 
                "/mnt/sdcard/folder2/d/file7.file", 
                "/mnt/sdcard/folder2/d/file8.file", 
                "/mnt/sdcard/file9.file" 
        };

        MXMTree tree = new MXMTree(new MXMNode("root", "root"));
        for (String data : slist) {
            tree.addElement(data);
        }

        tree.printTree();
    }

}

请告诉我你是否对改进有一些好的建议:)