45 lines
986 B
Java
45 lines
986 B
Java
// PART OF THE MACHINE SIMULATION. DO NOT CHANGE.
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package nachos.machine;
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/**
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* A read-only <tt>OpenFile</tt> backed by a byte array.
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*/
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public class ArrayFile extends OpenFileWithPosition {
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/**
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* Allocate a new <tt>ArrayFile</tt>.
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*
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* @param array the array backing this file.
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*/
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public ArrayFile(byte[] array) {
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this.array = array;
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}
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public int length() {
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return array.length;
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}
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public void close() {
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array = null;
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}
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public int read(int position, byte[] buf, int offset, int length) {
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Lib.assertTrue(offset >= 0 && length >= 0 && offset+length <= buf.length);
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if (position < 0 || position >= array.length)
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return 0;
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length = Math.min(length, array.length-position);
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System.arraycopy(array, position, buf, offset, length);
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return length;
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}
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public int write(int position, byte[] buf, int offset, int length) {
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return 0;
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}
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private byte[] array;
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}
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