Confirm code is correct - crossover methods in Java

I did this code for somebody but need it to be double checked before I pass it onto them. Code seems fine but I need someone to confirm I have coded the crossover methods correctly.

Would be great if somebody that is familiar with genetic algorithms and crossover methods, could confirm that I have the correct logic and code behind each crossover method.

//one crossover point is selected, string from beginning of chromosome to the 
 //crossover point is copied from one parent, the rest is copied from the second parent

 // One-point crossover

public void onePointCrossover(Individual indi) {
    if (SGA.rand.nextDouble()  xoverpoint2){
                tmp = xoverpoint;
                xoverpoint = xoverpoint2;
                xoverpoint2 = tmp;
            }

            for (int i=xoverpoint; i<xoverpoint2; i++){
                tmp = chromosome[i];
                chromosome[i] = indi.chromosome[i];
                indi.chromosome[i] = tmp;
            }   
        }   
    }

    //  For each gene, create a random number in [0,1]. If
    // the number is less than 0.5, swap the gene values in
    // the parents for this gene; otherwise, no swapping 

// Uniform Crossover
    public void UniformCrossover(Individual indi) {
        if (SGA.rand.nextDouble() < pc) {
        for (int i= 1; i<length; i++){
            boolean tmp =  SGA.rand.nextFloat() < 0.5;
            if(tmp){
                chromosome[i] = indi.chromosome[i];

            }
            }

        }

Parent 1 = chromosome Parent 2= indi.chromosome

I am turning the parents into children inplace.

It's difficult to just look at, but a few things jump out. More improvements than bugs:

-
For single point crossover using System.arraycopy() would be much more reliable. For example:

System.arraycopy(parent1Genes, 0, childGenes, 0, xoverPoint);
System.arraycopy(parent2Genes, xoverPoint, childGenes, xoverPoint, geneSize-xoverPoint);

-
You could use the same method for two point, but it would be slightly more complex.

-
In Uniform crossover you can use rand.nextBoolean(), which returns true or false, instead of comparing the float.

StackExchange Code Review Q#9077, answer score: 4