ReusableStringReader.java

package org.xbib.elasticsearch.index.analysis.combo;

import java.io.Reader;

final class ReusableStringReader extends Reader {
    private int pos = 0, size = 0;
    private String s = null;

    void setValue(String s) {
        this.s = s;
        this.size = s.length();
        this.pos = 0;
    }

    @Override
    public int read() {
        if (pos < size) {
            return s.charAt(pos++);
        } else {
            s = null;
            return -1;
        }
    }

    @Override
    public int read(char[] c, int off, int len) {
        if (pos < size) {
            len = Math.min(len, size - pos);
            s.getChars(pos, pos + len, c, off);
            pos += len;
            return len;
        } else {
            s = null;
            return -1;
        }
    }

    @Override
    public void close() {
        pos = size; // this prevents NPE when reading after close!
        s = null;
    }
}