//List the elements of the directory denoted by the given abstract //pathname. Return an array of strings naming the elements of the //directory if successful; otherwise, return <code>null</code>.
public abstract String[] list(File f);先看一下File的list方法,实际调用了FileSystem的list方法,上面是FileSystem.list(File f)的描述,意思是成功则返回给定路径下的所有元素名字的String数组,所以这里只有文件名public File(String pathname) { if (pathname == null) { throw new NullPointerException(); } this.path = fs.normalize(pathname); this.prefixLength = fs.prefixLength(this.path); } /** * Convert the given pathname string to normal form. If the string is * already in normal form then it is simply returned. */ public abstract String normalize(String path);再看File 构造函数,可以看出传进去的名字被FileSystem.normalize方法处理,看这个方法描述,将所给的路径转换成正常形式,如果是正常形式则简单返回,所以这里将文件名保存了 public String toString() { return getPath(); }File的toString() ,可以看出打印了path
这个代码因为注释的原因,导致我要问的问题不是很明显。再重新贴下代码 package myday20; import java.io.File; public class fileName{ public static void main(String[] args) throws Exception { File f = new File("src/myday20"); test1(f); System.out.println("------------------");
listMyFiles(f); } public static void test1(File file) { if (file.isDirectory()) { String[] s = file.list(); for (String string : s) { System.out.println(string); } System.out.println("--------------------------"); int length = s.length; File[] files = new File[length]; System.out.println(files.length); System.out.println(files[0]); // files[0] = new File(s[0]); // System.out.println(files[0]);// 这里输出的为什么是文件名字而不是地址? System.out.println("----------------------");
for (int i = 0; i < length - 1; i++) { files[i] = new File(s[i]); System.out.println(files[i]); System.out.println(files[i].canExecute()); System.out.println(files[i].exists()); System.out.println("------------------"); } for (int i = 0; i < length - 1; i++) { test1(files[i]); } } } public static void listMyFiles(File file) {
if (file.isDirectory()) { File[] fs = file.listFiles(); for (File file2 : fs) { System.out.println(file2); System.out.println(file2.exists()); } for (File file2 : fs) { listMyFiles(file2); } } } }
这个代码因为注释的原因,导致我要问的问题不是很明显。再重新贴下代码 package myday20; import java.io.File; public class fileName{ public static void main(String[] args) throws Exception { File f = new File("src/myday20"); test1(f); System.out.println("------------------");
listMyFiles(f); } public static void test1(File file) { if (file.isDirectory()) { String[] s = file.list(); for (String string : s) { System.out.println(string); } System.out.println("--------------------------"); int length = s.length; File[] files = new File[length]; System.out.println(files.length); System.out.println(files[0]); // files[0] = new File(s[0]); // System.out.println(files[0]);// 这里输出的为什么是文件名字而不是地址? System.out.println("----------------------");
for (int i = 0; i < length - 1; i++) { files[i] = new File(s[i]); System.out.println(files[i]); System.out.println(files[i].canExecute()); System.out.println(files[i].exists()); System.out.println("------------------"); } for (int i = 0; i < length - 1; i++) { test1(files[i]); } } } public static void listMyFiles(File file) {
if (file.isDirectory()) { File[] fs = file.listFiles(); for (File file2 : fs) { System.out.println(file2); System.out.println(file2.exists()); } for (File file2 : fs) { listMyFiles(file2); } } } } 我这个代码的目的是要找出myday20文件夹下的所有文件
//List the elements of the directory denoted by the given abstract
//pathname. Return an array of strings naming the elements of the
//directory if successful; otherwise, return <code>null</code>.
public abstract String[] list(File f);先看一下File的list方法,实际调用了FileSystem的list方法,上面是FileSystem.list(File f)的描述,意思是成功则返回给定路径下的所有元素名字的String数组,所以这里只有文件名public File(String pathname) {
if (pathname == null) {
throw new NullPointerException();
}
this.path = fs.normalize(pathname);
this.prefixLength = fs.prefixLength(this.path);
} /**
* Convert the given pathname string to normal form. If the string is
* already in normal form then it is simply returned.
*/
public abstract String normalize(String path);再看File 构造函数,可以看出传进去的名字被FileSystem.normalize方法处理,看这个方法描述,将所给的路径转换成正常形式,如果是正常形式则简单返回,所以这里将文件名保存了 public String toString() {
return getPath();
}File的toString() ,可以看出打印了path
package myday20;
import java.io.File;
public class fileName{ public static void main(String[] args) throws Exception { File f = new File("src/myday20");
test1(f);
System.out.println("------------------");
listMyFiles(f);
} public static void test1(File file) {
if (file.isDirectory()) {
String[] s = file.list();
for (String string : s) {
System.out.println(string);
}
System.out.println("--------------------------");
int length = s.length;
File[] files = new File[length];
System.out.println(files.length);
System.out.println(files[0]);
// files[0] = new File(s[0]);
// System.out.println(files[0]);// 这里输出的为什么是文件名字而不是地址?
System.out.println("----------------------");
for (int i = 0; i < length - 1; i++) {
files[i] = new File(s[i]);
System.out.println(files[i]);
System.out.println(files[i].canExecute());
System.out.println(files[i].exists());
System.out.println("------------------");
}
for (int i = 0; i < length - 1; i++) {
test1(files[i]);
}
}
} public static void listMyFiles(File file) {
if (file.isDirectory()) {
File[] fs = file.listFiles();
for (File file2 : fs) {
System.out.println(file2);
System.out.println(file2.exists());
}
for (File file2 : fs) {
listMyFiles(file2);
}
}
}
}
package myday20;
import java.io.File;
public class fileName{ public static void main(String[] args) throws Exception { File f = new File("src/myday20");
test1(f);
System.out.println("------------------");
listMyFiles(f);
} public static void test1(File file) {
if (file.isDirectory()) {
String[] s = file.list();
for (String string : s) {
System.out.println(string);
}
System.out.println("--------------------------");
int length = s.length;
File[] files = new File[length];
System.out.println(files.length);
System.out.println(files[0]);
// files[0] = new File(s[0]);
// System.out.println(files[0]);// 这里输出的为什么是文件名字而不是地址?
System.out.println("----------------------");
for (int i = 0; i < length - 1; i++) {
files[i] = new File(s[i]);
System.out.println(files[i]);
System.out.println(files[i].canExecute());
System.out.println(files[i].exists());
System.out.println("------------------");
}
for (int i = 0; i < length - 1; i++) {
test1(files[i]);
}
}
} public static void listMyFiles(File file) {
if (file.isDirectory()) {
File[] fs = file.listFiles();
for (File file2 : fs) {
System.out.println(file2);
System.out.println(file2.exists());
}
for (File file2 : fs) {
listMyFiles(file2);
}
}
}
}
我这个代码的目的是要找出myday20文件夹下的所有文件