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分享文件拷贝，重现重复内容怎么办
我想通过一个程序复制一个java文件，也就是将 A.java 复制到 B.java 中去，
但是再复制的时候，出现了重复出现的情况，
也就是，程序好像讲缓冲区前面的部分重新写了一遍
大家说说应该怎么解决呢，嗯，上代码
只选取了文件的结尾部分
只选取了文件的结尾部分
但是再复制的时候，出现了重复出现的情况，
也就是，程序好像讲缓冲区前面的部分重新写了一遍
大家说说应该怎么解决呢，嗯，上代码
//复制的代码，感觉在缓冲区的时候有点问题
class FileCopy
{
FileInputStream FIS;
FileOutputStream FOS;
public boolean copyFile(File src, File des) {
try {
FIS = new FileInputStream(src);
} catch (FileNotFoundException e) {
// TODO Auto-generated catch block
e.printStackTrace();
}
try {
FOS = new FileOutputStream(des);
} catch (FileNotFoundException e) {
// TODO Auto-generated catch block
e.printStackTrace();
}
byte[] bt = new byte[1024];
int readNum = 0;
try {
while( (readNum = FIS.read(bt)) != -1 ) {
FOS.write(bt, 0,bt.length);
}
} catch (IOException e) {
// TODO Auto-generated catch block
e.printStackTrace();
}
try {
FIS.close();
} catch (IOException e) {
// TODO Auto-generated catch block
e.printStackTrace();
}
try {
FOS.close();
} catch (IOException e) {
// TODO Auto-generated catch block
e.printStackTrace();
}
return true;
}
}
只选取了文件的结尾部分
public class register_inquiry extends Domain
{
public register_inquiry()
{
TermVariable.initialize(2);
constants = new String[3];
constants[0] = "in";
constants[1] = "information";
constants[2] = "tool";
compoundTasks = new String[1];
compoundTasks[0] = "register_inquiry";
primitiveTasks = new String[1];
primitiveTasks[0] = "!register";
methods = new Method[1][];
methods[0] = new Method[1];
methods[0][0] = new Method0();
ops = new Operator[1][];
ops[0] = new Operator[1];
ops[0][0] = new Operator0();
axioms = new Axiom[3][];
axioms[0] = new Axiom[0];
axioms[1] = new Axiom[0];
axioms[2] = new Axiom[0];
}
}
只选取了文件的结尾部分
public class register_inquiry extends Domain
{
public register_inquiry()
{
TermVariable.initialize(2);
constants = new String[3];
constants[0] = "in";
constants[1] = "information";
constants[2] = "tool";
compoundTasks = new String[1];
compoundTasks[0] = "register_inquiry";
primitiveTasks = new String[1];
primitiveTasks[0] = "!register";
methods = new Method[1][];
methods[0] = new Method[1];
methods[0][0] = new Method0();
ops = new Operator[1][];
ops[0] = new Operator[1];
ops[0][0] = new Operator0();
axioms = new Axiom[3][];
axioms[0] = new Axiom[0];
axioms[1] = new Axiom[0];
axioms[2] = new Axiom[0];
}
}
//重复出现的部分
switch (which)
{
case 0:
p = (new Precondition0(unifier)).setComparator(null);
break;
default:
return null;
}
p.reset();
return p;
}
public String getLabel(int which)
{
switch (which)
{
case 0: return "Method0Branch0";
default: return null;
}
}
}
public class reg
//重复出现的情况结束
...全文
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BearKin 2010-02-22
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LZ可换字符流来读
恩 内容太短了
恩 内容太短了
ScAREcrOw_ss 2010-02-22
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public boolean copyFile(File src, File des) {
FileInputStream fis = null;
FileOutputStream fos = null;
try {
fis = new FileInputStream(src);
fos = new FileOutputStream(des);
byte[] bt = new byte[1024];
int readNum = 0;
while ((readNum = fis.read(bt)) != -1) {
fos.write(bt, 0, readNum);
}
} catch (FileNotFoundException e) {
e.printStackTrace();
return false;
} catch (IOException e) {
e.printStackTrace();
return false;
} finally {
try {
if(fis!=null)
fis.close();
if(fos!=null)
fos.close();
} catch (IOException e) {
e.printStackTrace();
return false;
}
}
return true;
}
zhaining522 2010-02-22
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不过 一个理想方式是
直接连接2个FileChannel 通道
直接连接2个FileChannel 通道
public class FileCopy
{
FileInputStream FIS;
FileOutputStream FOS;
public boolean copyFile(File src, File des) {
try {
FIS = new FileInputStream(src);
} catch (FileNotFoundException e) {
// TODO Auto-generated catch block
e.printStackTrace();
}
try {
FOS = new FileOutputStream(des);
} catch (FileNotFoundException e) {
// TODO Auto-generated catch block
e.printStackTrace();
}
// byte[] bt = new byte[1024];
ByteBuffer buffer = ByteBuffer.allocate(1024);
FileChannel in = FIS.getChannel(),
out = FOS.getChannel();
try {
in.transferTo(0, in.size(), out);
} catch (IOException e1) {
// TODO Auto-generated catch block
e1.printStackTrace();
}
// int readNum = 0;
// try {
// while( (readNum = in.read(buffer)) != -1 ) {
// buffer.flip();
// out.write(buffer);
// buffer.clear();
//// FOS.write(bt, 0,bt.length);
//// bt = new byte[1024];
// }
// } catch (IOException e) {
// // TODO Auto-generated catch block
// e.printStackTrace();
// }
try {
in.close();
} catch (IOException e) {
// TODO Auto-generated catch block
e.printStackTrace();
}
try {
out.close();
} catch (IOException e) {
// TODO Auto-generated catch block
e.printStackTrace();
}
return true;
}
public static void main(String []args){
File file1 = new File("demo.txt");
File file2 = new File("demodemo.txt");
System.out.println(new FileCopy().copyFile(file1,file2));
}
}
zhaining522 2010-02-22
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或者 用 FileChannel 加上 字节缓存区 ByteBuffer
这样比较好
这样比较好
package File.IO;
import java.io.File;
import java.io.FileInputStream;
import java.io.FileNotFoundException;
import java.io.FileOutputStream;
import java.io.IOException;
import java.nio.ByteBuffer;
import java.nio.channels.FileChannel;
public class FileCopy
{
FileInputStream FIS;
FileOutputStream FOS;
public boolean copyFile(File src, File des) {
try {
FIS = new FileInputStream(src);
} catch (FileNotFoundException e) {
// TODO Auto-generated catch block
e.printStackTrace();
}
try {
FOS = new FileOutputStream(des);
} catch (FileNotFoundException e) {
// TODO Auto-generated catch block
e.printStackTrace();
}
// byte[] bt = new byte[1024];
ByteBuffer buffer = ByteBuffer.allocate(1024);
FileChannel in = FIS.getChannel(),
out = FOS.getChannel();
int readNum = 0;
try {
while( (readNum = in.read(buffer)) != -1 ) {
buffer.flip();
out.write(buffer);
buffer.clear();
// FOS.write(bt, 0,bt.length);
// bt = new byte[1024];
}
} catch (IOException e) {
// TODO Auto-generated catch block
e.printStackTrace();
}
try {
in.close();
} catch (IOException e) {
// TODO Auto-generated catch block
e.printStackTrace();
}
try {
out.close();
} catch (IOException e) {
// TODO Auto-generated catch block
e.printStackTrace();
}
return true;
}
public static void main(String []args){
File file1 = new File("demo.txt");
File file2 = new File("demodemo.txt");
System.out.println(new FileCopy().copyFile(file1,file2));
}
}
zhaining522 2010-02-22
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class FileCopy
{
FileInputStream FIS;
FileOutputStream FOS;
public boolean copyFile(File src, File des) {
try {
FIS = new FileInputStream(src);
} catch (FileNotFoundException e) {
// TODO Auto-generated catch block
e.printStackTrace();
}
try {
FOS = new FileOutputStream(des);
} catch (FileNotFoundException e) {
// TODO Auto-generated catch block
e.printStackTrace();
}
byte[] bt = new byte[1024];
int readNum = 0;
try {
while( (readNum = FIS.read(bt)) != -1 ) {
FOS.write(bt, 0,bt.length);
bt = new byte[1024];
}
} catch (IOException e) {
// TODO Auto-generated catch block
e.printStackTrace();
}
try {
FIS.close();
} catch (IOException e) {
// TODO Auto-generated catch block
e.printStackTrace();
}
try {
FOS.close();
} catch (IOException e) {
// TODO Auto-generated catch block
e.printStackTrace();
}
return true;
}
}
BearKin 2010-02-22
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用字符流 先将所有内容读进来 然后查找需要更换的地方 替换完毕后再写入
分给我吧 表给LS的
zhaining522 2010-02-22
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在问问提就另开个贴
这个贴 可以结贴了
这个贴 可以结贴了
Eniak 2010-02-22
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谢谢各位，再问个问题，如果我想在一个特定的位置加入一个字符串呢，比如
在文件出现 "abcde" 的时候加入这个字符，但是不知道何时出现，如果出出现了，就在 "abcde" 的前面加上 "AAA_" 后面加上 "_BBB"， 最后的结果就是 “AAA_abcde_BBB”， 文件只是这么改动一下，AAA_abcde_BBB” 后面的部分继续复制
这个应该则么改呢？
在文件出现 "abcde" 的时候加入这个字符，但是不知道何时出现，如果出出现了，就在 "abcde" 的前面加上 "AAA_" 后面加上 "_BBB"， 最后的结果就是 “AAA_abcde_BBB”， 文件只是这么改动一下，AAA_abcde_BBB” 后面的部分继续复制
这个应该则么改呢？
