對Reader進(jìn)行token的類,可以訪入多個split進(jìn)行解析
2024-07-21 02:15:23
供稿:網(wǎng)友
在java。util中的java.io.stringtokenizer類能對單個字符串進(jìn)行解析,在jdk1.4中的split也可以對單個字符串進(jìn)行解析,但都不能對reader流進(jìn)行解析,在多個字符解析的時候也不能返回分割兩個字符串的字符串,下面這個類就是為了解決這個問題而寫的,還可以在準(zhǔn)備包括一些最基本的解析類型,*和?
可以設(shè)置多個split進(jìn)行解析,在解析的時候返回對應(yīng)的分割字符串
程序可以直接運行
/* * 創(chuàng)建日期 2005-4-4 * * 更改所生成文件模板為 * 窗口 > 首選項 > java > 代碼生成 > 代碼和注釋 */package com.csii.template;
import java.io.ioexception;import java.io.inputstreamreader;import java.io.reader;import java.io.stringreader;import java.util.iterator;
/** * @author wsl * * 更改所生成類型注釋的模板為 * 窗口 > 首選項 > java > 代碼生成 > 代碼和注釋 */public class readertoken implements iterator {
private reader reader = null;//存放準(zhǔn)備解析的字符流 private string[] splits = null;//準(zhǔn)備用來分割字符流的token private stringbuffer hasread = new stringbuffer();//存放從流中已經(jīng)讀的字符 private string[] splitssf = null;//由于可能存在一些統(tǒng)配符,所以此處存放統(tǒng)配符在token時的字符,比如在abcdefgh /** * */ public readertoken(reader reader, string[] split) { super(); this.reader = reader; this.splits = split; splitssf = new string[split.length]; for (int i = 0; i < split.length; i++) { splitssf[i] = ""; } }
/* (非 javadoc) * @see java.util.iterator#hasnext() */ public boolean hasnext() { if (indexof() > -1) { return true; } return false; } private int currentsplit = -1; private int indexof() {
currentsplit = -1; int[] pos = new int[splits.length]; for (int i = 0; i < pos.length; i++) { splitssf[i] = ""; pos[i] = 0; } //初試位置符號
try { while (true) {
for (int j = 0; j < pos.length; j++) { if (pos[j] >= splits[j].length()) { currentsplit = j;
return currentsplit;
//如果當(dāng)前pos里面的長度達(dá)到最splits里面的最大值,返回當(dāng)前的split } }
char readchar = (char) reader.read();
if (readchar == -1) { return currentsplit; }
if (readchar == 65535) { return currentsplit; }
hasread.append(readchar);
for (int i = 0; i < pos.length; i++) {
char splitposchar = splits[i].charat(pos[i]);
if (splitposchar == readchar) { pos[i]++; splitssf[i] += readchar; } else if (splitposchar == '*') { char nextchar = splits[i].charat((pos[i] + 1)); //得到*后面一個字符,一般統(tǒng)配符都表示為1*2 if (nextchar == readchar) { pos[i]++; pos[i]++; } splitssf[i] += readchar; } else if (splitposchar == '?') { pos[i]++; splitssf[i] += readchar; } else {
pos[i] = 0; splitssf[i] = ""; }
}
}
} catch (ioexception e) {
e.printstacktrace(); }
return -1; }
/* (非 javadoc) * @see java.util.iterator#next() */ public object next() {
int i = hasread.length() - splitssf[currentsplit].length();
stringbuffer sf = new stringbuffer(); sf = this.hasread; hasread = new stringbuffer(); // if(i<0){ // i=0; // } sf.setlength(i); return sf;
} public string gettoken() { return splits[this.currentsplit]; } public string gettokeninreader() { return splitssf[currentsplit]; } public object getend() { return this.hasread; } /* (非 javadoc) * @see java.util.iterator#remove() */ public void remove() {
} public static void main(string[] args) throws ioexception { string[] a = new string[] { "a?a" }; string s = "cefaaasdbd"; readertoken token = new readertoken(new stringreader(s), a); while (token.hasnext()) { system.err.println("next---" + token.next()); system.err.println("token---" + token.gettoken()); system.err.println( "gettokeninreader---" + token.gettokeninreader()); } system.err.println("end--" + token.getend());
// stringreader reader=new stringreader(s); // char c; // while((c=(char)reader.read())!=-1){ // system.err.println(c); // system.out.println((long)c); // }
}}