FileReader、FileWriter 操作，从文件读取出来，在组合读入文件

import java.io.File;
import java.io.FileReader;
import java.io.FileWriter;

public class MainClass{
public static void main(String[] args) throws Exception{
FileManager a = new FileManager("a.txt",new char[]{'\n'});
FileManager b = new FileManager("b.txt",new char[]{'\n',' '});
FileWriter c = new FileWriter("c.txt");
String aWord = null;
String bWord = null;
while((aWord = a.nextWord()) !=null ){
c.write(aWord + "\n");
bWord = b.nextWord();
if(bWord != null)
c.write(bWord + "\n");
}

while((bWord = b.nextWord()) != null){
c.write(bWord + "\n");
}
c.close();
}

}

class FileManager{

String[] words = null;
int pos = 0;
public FileManager(String filename,char[] seperators) throws Exception{
File f = new File(filename);
FileReader reader = new FileReader(f);
char[] buf = new char[(int)f.length()];
int len = reader.read(buf); //将字符读入数组buf，返回值为读取的字符数，此时buf里面已经存放的是filename指定路径文本的内容
String results = new String(buf,0,len);
String regex = null;
if(seperators.length >1 ){
regex = "" + seperators[0] + "|" + seperators[1];
}else{
regex = "" + seperators[0];
}
words = results.split(regex);
}

public String nextWord(){
if(pos == words.length)
return null;
return words[pos++];
}

}