org.datagator.api.client.MatrixDeserializer.java Source code

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Here is the source code for org.datagator.api.client.MatrixDeserializer.java

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/*
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package org.datagator.api.client;

import com.fasterxml.jackson.core.JsonParser;
import com.fasterxml.jackson.core.JsonProcessingException;
import com.fasterxml.jackson.core.JsonToken;
import com.fasterxml.jackson.databind.DeserializationContext;
import com.fasterxml.jackson.databind.JsonDeserializer;
import java.io.IOException;
import java.util.ArrayList;

/**
 *
 * @author liuyu
 */
class MatrixDeserializer extends JsonDeserializer<SimpleMatrix> {

    private static ArrayList<ArrayList<Object>> parseRows(JsonParser jp, int bodyRow, int bodyColumn)
            throws IOException, JsonProcessingException {
        ArrayList<ArrayList<Object>> columnHeaders = new ArrayList<ArrayList<Object>>();

        int rowIndex = 0;

        JsonToken token = jp.getCurrentToken(); // START_ARRAY
        if (!token.equals(JsonToken.START_ARRAY)) {
            throw new RuntimeException(String.format("Unexpected token %s", token));
        }

        token = jp.nextToken(); // START_ARRAY
        while (token.equals(JsonToken.START_ARRAY)) {
            int columnIndex = 0;
            if (rowIndex < bodyRow) {
                ArrayList<Object> rowBuffer = new ArrayList<Object>();
                token = jp.nextToken();
                while (!token.equals(JsonToken.END_ARRAY)) {
                    rowBuffer.add(jp.getText());
                    columnIndex += 1;
                    token = jp.nextToken();
                }
                columnHeaders.add(rowBuffer);
            } else {
                token = jp.nextToken();
                while (!token.equals(JsonToken.END_ARRAY)) {
                    columnIndex += 1;
                    token = jp.nextToken();
                }
            }
            rowIndex += 1;
            token = jp.nextToken(); // START_ARRAY
        }

        return columnHeaders;
    }

    @Override
    public SimpleMatrix deserialize(JsonParser jp, DeserializationContext cntx)
            throws IOException, JsonProcessingException {
        int rowsCount = -1;
        int columnsCount = -1;
        int bodyRow = -1;
        int bodyColumn = -1;

        ArrayList<ArrayList<Object>> columnHeaders = null;

        JsonToken token = jp.getCurrentToken(); // FIELD_NAME
        if (!token.equals(JsonToken.FIELD_NAME)) {
            throw new RuntimeException(String.format("Unexpected token %s", token));
        }
        while (token.equals(JsonToken.FIELD_NAME)) {
            String name = jp.getText();
            token = jp.nextToken();
            if (name.equals("columnHeaders")) {
                if (!token.equals(JsonToken.VALUE_NUMBER_INT)) {
                    throw new RuntimeException(String.format("Unexpected token %s", token));
                }
                bodyRow = jp.getIntValue();
            } else if (name.equals("rowHeaders")) {
                if (!token.equals(JsonToken.VALUE_NUMBER_INT)) {
                    throw new RuntimeException(String.format("Unexpected token %s", token));
                }
                bodyColumn = jp.getIntValue();
            } else if (name.equals("rows")) {
                if (bodyRow < 0 || bodyColumn < 0) {
                    throw new RuntimeException(
                            "Unexpected property order 'columnHeaders' and 'rowHeaders' should precede 'rows'.");
                }
                columnHeaders = parseRows(jp, bodyRow, bodyColumn);
            } else if (name.equals("rowsCount")) {
                if (!token.equals(JsonToken.VALUE_NUMBER_INT)) {
                    throw new RuntimeException(String.format("Unexpected token %s", token));
                }
                rowsCount = jp.getIntValue();
            } else if (name.equals("columnsCount")) {
                if (!token.equals(JsonToken.VALUE_NUMBER_INT)) {
                    throw new RuntimeException(String.format("Unexpected token %s", token));
                }
                columnsCount = jp.getIntValue();
            } else {
                throw new RuntimeException(String.format("Unexpected property '%s'", name));
            }
            token = jp.nextToken(); // FIELD_NAME
        }

        if (!(0 <= bodyRow && bodyRow <= rowsCount)) {
            throw new RuntimeException("Invalid Matrix shape");
        }

        if (!(0 <= bodyColumn && bodyColumn <= columnsCount)) {
            throw new RuntimeException("Invalid Matrix shape");
        }

        // special case: size of empty matrix is 1 x 0
        if ((columnsCount == 0) && (rowsCount != 1)) {
            throw new RuntimeException("Invalid Matrix shape");
        }

        Object[][] rows = new Object[bodyRow][];
        for (int r = 0; r < bodyRow; r++) {
            rows[r] = columnHeaders.get(r).toArray();
        }

        return new SimpleMatrix(bodyRow, bodyColumn, rows, rowsCount, columnsCount);
    }

};